chore(userspace/libsinsp): only link libanl if present.

[FedeDP]

What type of PR is this?

/kind cleanup

Any specific area of the project related to this PR?

/area libsinsp

Does this PR require a change in the driver versions?

What this PR does / why we need it:

libanl is only available for glibc; only link it when it is present in the system.
Also, this is another step forward to support building libs with zig compiler.

Which issue(s) this PR fixes:

Fixes #1948

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

NONE

[FedeDP]

Putting this in milestone 0.19.
/milestone 0.19.0

[github-actions]

Perf diff from master - unit tests

     3.14%     +1.19%  [.] sinsp_thread_manager::get_thread_ref
     6.65%     +0.96%  [.] sinsp::next
     5.72%     -0.81%  [.] next
     1.27%     +0.73%  [.] std::_Hashtable<long, std::pair<long const, std::shared_ptr<sinsp_threadinfo> >, std::allocator<std::pair<long const, std::shared_ptr<sinsp_threadinfo> > >, std::__detail::_Select1st, std::equal_to<long>, std::hash<long>, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits<false, false, true> >::_M_find_before_node
     3.50%     -0.63%  [.] sinsp_thread_manager::find_thread
     9.57%     +0.60%  [.] sinsp_parser::reset
     1.20%     -0.52%  [.] sinsp_evt::get_direction
     0.21%     +0.42%  [.] scap_cgroup_resolve_v2
     0.81%     +0.40%  [.] 0x00000000000e93c0
     0.22%     +0.40%  [.] sinsp_parser::parse_clone_exit_child

Heap diff from master - unit tests

peak heap memory consumption: 0B
peak RSS (including heaptrack overhead): 0B
total memory leaked: 0B

Heap diff from master - scap file

peak heap memory consumption: 0B
peak RSS (including heaptrack overhead): 0B
total memory leaked: 0B

Benchmarks diff from master

Comparing gbench_data.json to /root/actions-runner/_work/libs/libs/build/gbench_data.json
Benchmark                                                         Time             CPU      Time Old      Time New       CPU Old       CPU New
----------------------------------------------------------------------------------------------------------------------------------------------
BM_sinsp_split_mean                                            +0.0352         +0.0353           145           151           145           151
BM_sinsp_split_median                                          +0.0382         +0.0383           145           151           145           151
BM_sinsp_split_stddev                                          +0.2012         +0.1990             1             1             1             1
BM_sinsp_split_cv                                              +0.1603         +0.1581             0             0             0             0
BM_sinsp_concatenate_paths_relative_path_mean                  +0.1720         +0.1721            42            49            42            49
BM_sinsp_concatenate_paths_relative_path_median                +0.1874         +0.1875            42            50            42            50
BM_sinsp_concatenate_paths_relative_path_stddev                +2.2457         +2.2446             0             1             0             1
BM_sinsp_concatenate_paths_relative_path_cv                    +1.7694         +1.7682             0             0             0             0
BM_sinsp_concatenate_paths_empty_path_mean                     -0.0143         -0.0142            17            17            17            17
BM_sinsp_concatenate_paths_empty_path_median                   -0.0163         -0.0161            17            17            17            17
BM_sinsp_concatenate_paths_empty_path_stddev                   +0.1341         +0.1334             0             0             0             0
BM_sinsp_concatenate_paths_empty_path_cv                       +0.1505         +0.1498             0             0             0             0
BM_sinsp_concatenate_paths_absolute_path_mean                  +0.1577         +0.1578            43            50            43            50
BM_sinsp_concatenate_paths_absolute_path_median                +0.1581         +0.1582            43            50            43            50
BM_sinsp_concatenate_paths_absolute_path_stddev                -0.2176         -0.2166             0             0             0             0
BM_sinsp_concatenate_paths_absolute_path_cv                    -0.3242         -0.3233             0             0             0             0
BM_sinsp_split_container_image_mean                            -0.0037         -0.0036           349           347           349           347
BM_sinsp_split_container_image_median                          -0.0062         -0.0061           350           347           349           347
BM_sinsp_split_container_image_stddev                          -0.1194         -0.1197             3             3             3             3
BM_sinsp_split_container_image_cv                              -0.1162         -0.1165             0             0             0             0

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 74.31%. Comparing base (e2c5174) to head (3f713fa).
Report is 28 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #2036   +/-   ##
=======================================
  Coverage   74.31%   74.31%           
=======================================
  Files         253      253           
  Lines       30966    30966           
  Branches     5403     5393   -10     
=======================================
  Hits        23011    23011           
+ Misses       7942     7927   -15     
- Partials       13       28   +15     

Flag	Coverage Δ
libsinsp	74.31% <ø> (ø)

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[Andreagit97]

/approve

[poiana]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Andreagit97, FedeDP

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• OWNERS [Andreagit97,FedeDP]

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[FedeDP]

/milestone 0.18.0