crypto: ccp - Abort doing SEV INIT if SNP INIT fails

If SNP host support (SYSCFG.SNPEn) is set, then the RMP table must
be initialized before calling SEV INIT.

In other words, if SNP_INIT(_EX) is not issued or fails then
SEV INIT will fail if SNP host support (SYSCFG.SNPEn) is enabled.

Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>