crypto: testmgr - remove crc32c context format test

This is no longer needed now that the code that used to directly access
the descriptor context of "crc32c" (libcrc32c and ext4) now just calls
crc32c().  Keep just the generic hash test.

Link: https://lore.kernel.org/r/20250531205937.63008-1-ebiggers@kernel.org


Signed-off-by: Eric Biggers <ebiggers@kernel.org>