A few fixes needed to pass gating. Some failures were also fixed in
the testsuite.
- Threadsnoop need to points to libpthread.so.0 instead of
libpthread.so
- aarch64 specific fixes: some syscall are not present on all arches.
Related: rhbz#1967567
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
