Re: [PATCH] crypto: RNGs must return 0 in success case

Change the RNGs to always return 0 in success case.

This patch ensures that seqiv.c works with RNGs other than krng. seqiv
expects that any return code other than 0 is an error. Without the
patch, rfc4106(gcm(aes)) will not work when using a DRBG or an ANSI
X9.31 RNG.

For the X9.31 bits:
Acked-by: Neil Horman <nhorman@tuxdriver.com>