crypto: hash - Hide CRYPTO_ALG_TYPE_AHASH_MASK

Move the macro CRYPTO_ALG_TYPE_AHASH_MASK out of linux/crypto.h
and into crypto/ahash.c so that it's not visible to users of the
Crypto API.

Also remove the unused CRYPTO_ALG_TYPE_HASH_MASK macro.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>