ANDROID: fips140: add crypto_memneq() back to the module

crypto_memneq() is one of the utility functions that was intentionally
included in the fips140 module, out of concerns that it would be seen as
"cryptographic" and thus would be required to be included the module for
the FIPS certification.  It should not have been removed from the
module, so add it back.

Bug: 188620248
Fixes: 29c42766 ("Merge tag 'android13-5.10.149_r00' into android13-5.10")
Change-Id: I8a19dfd73390f8c1348885f97fa42d900e47b82b
Signed-off-by: Eric Biggers <ebiggers@google.com>