[CRYPTO] api: Set default CRYPTO_MINALIGN to unsigned long long

Thanks to David Miller for pointing out that the SLAB (or SLOB/SLUB)
cache uses the alignment of unsigned long long if the architecture
kmalloc/slab alignment macros are not defined.

This patch changes the CRYPTO_MINALIGN so that it uses the same default
value.

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