bpf: Selftests, provide verbose option for selftests execution

Pass options from command line args into individual tests which allows us
to use verbose option from command line with selftests. Now when verbose
option is set individual subtest details will be printed. Also we can
consolidate cgroup bring up and tear down.

Additionally just setting verbose is very noisy so introduce verbose=1
and verbose=2. Really verbose=2 is only useful when developing tests
or debugging some specific issue.

For example now we get output like this with --verbose,

#20/17 sockhash:txmsg test pull-data:OK
 [TEST 160]: (512, 1, 3, sendpage, pop (1,3),): msg_loop_rx: iov_count 1 iov_buf 1 cnt 512 err 0
 [TEST 161]: (100, 1, 5, sendpage, pop (1,3),): msg_loop_rx: iov_count 1 iov_buf 3 cnt 100 err 0
 [TEST 162]: (2, 1024, 256, sendpage, pop (4096,8192),): msg_loop_rx: iov_count 1 iov_buf 255 cnt 2 err 0
 [TEST 163]: (512, 1, 3, sendpage, redir,pop (1,3),): msg_loop_rx: iov_count 1 iov_buf 1 cnt 512 err 0
 [TEST 164]: (100, 1, 5, sendpage, redir,pop (1,3),): msg_loop_rx: iov_count 1 iov_buf 3 cnt 100 err 0
 [TEST 165]: (512, 1, 3, sendpage, cork 512,pop (1,3),): msg_loop_rx: iov_count 1 iov_buf 1 cnt 512 err 0
 [TEST 166]: (100, 1, 5, sendpage, cork 512,pop (1,3),): msg_loop_rx: iov_count 1 iov_buf 3 cnt 100 err 0
 [TEST 167]: (512, 1, 3, sendpage, redir,cork 4,pop (1,3),): msg_loop_rx: iov_count 1 iov_buf 1 cnt 512 err 0
 [TEST 168]: (100, 1, 5, sendpage, redir,cork 4,pop (1,3),): msg_loop_rx: iov_count 1 iov_buf 3 cnt 100 err 0

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/158939730412.15176.1975675235035143367.stgit@john-Precision-5820-Tower