tests: Skip testing 1024 bits key generation in FIPS mode

In torture_threads_pki_rsa, skip the test which generates 1024 bits RSA
key pair when in FIPS mode.

Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
(cherry picked from commit 3a61cd34a90d758262d63ecb01a0cc65d0abe90e)