Expand the BPF sockopt test to use also check for io_uring
{g,s}etsockopt commands operations.
Create infrastructure to run io_uring tests using the mini_liburing
helpers, so, the {g,s}etsockopt operation could either be called from
system calls, or, via io_uring.
Add a 'use_io_uring' parameter to run_test(), to specify if the test
should be run using io_uring if the parameter is set, or via the regular
system calls if false.
Call *all* tests twice, using the regular io_uring path, and the new
io_uring path.