Return sysvars via syscalls (bp #16422)

[mergify]

This is an automatic backport of pull request #16422 done by Mergify.

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Changes to be committed:
	modified:   Cargo.lock
	modified:   program-test/src/lib.rs
	new file:   program-test/tests/sysvar.rs
	modified:   programs/bpf_loader/src/syscalls.rs
	modified:   runtime/src/bank.rs
	modified:   runtime/src/message_processor.rs
	modified:   sdk/program/src/clock.rs
	modified:   sdk/program/src/program_stubs.rs
	modified:   sdk/program/src/sysvar/clock.rs
	modified:   sdk/program/src/sysvar/epoch_schedule.rs
	modified:   sdk/program/src/sysvar/fees.rs
	modified:   sdk/program/src/sysvar/mod.rs
	modified:   sdk/program/src/sysvar/rent.rs
	modified:   sdk/src/feature_set.rs
	modified:   sdk/src/process_instruction.rs

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   program-test/Cargo.toml
	both modified:   programs/bpf/Cargo.lock
	both modified:   programs/bpf/rust/sysvar/src/lib.rs

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[mergify]

automerge label removed due to a CI failure

[mergify]

automerge label removed due to a CI failure

[mvines]

Maybe a missing backport?

error[E0433]: failed to resolve: use of undeclared crate or module `rent`
--
  | --> rust/sysvar/src/lib.rs:92:9
  | \|
  | 92 \|         rent::DEFAULT_LAMPORTS_PER_BYTE_YEAR * rent::DEFAULT_EXEMPTION_THRESHOLD as u64,
  | \|         ^^^^ use of undeclared crate or module `rent`

[mergify]

automerge label removed due to a CI failure

[mergify]

automerge label removed due to a CI failure

[mvines]

Close, test_program_bpf_sanity is failing

[mergify]

automerge label removed due to a CI failure

[mergify]

automerge label removed due to a CI failure

[codecov]

Codecov Report

Merging #16497 (7ca41f4) into v1.6 (97ba3cb) will decrease coverage by 0.0%.
The diff coverage is 65.0%.

@@            Coverage Diff            @@
##             v1.6   #16497     +/-   ##
=========================================
- Coverage    80.0%    79.9%   -0.1%     
=========================================
  Files         413      413             
  Lines      110986   111228    +242     
=========================================
+ Hits        88824    88977    +153     
- Misses      22162    22251     +89     

[mvines]

@jackcmay - it looks like this PR wasn't rebased on #16515 and now the tip of v1.6 is broken. Check out https://buildkite.com/solana-labs/solana/builds/44116#job-d1519a2e-bbda-45fb-99c0-521bb41a8ee0

[jackcmay]

@jackcmay - it looks like this PR wasn't rebased on #16515 and now the tip of v1.6 is broken. Check out https://buildkite.com/solana-labs/solana/builds/44116#job-d1519a2e-bbda-45fb-99c0-521bb41a8ee0

Hopefully fixed vis #16535