crypto: hash - Fix kdoc errors about HASH_ALG_COMMON

The HASH_ALG_COMMON macro cannot be parsed by kdoc so mark it as
a normal comment instead of kdoc.  Also add HASH_ALG_COMMON as a
structure member of shash_alg.

Fixes: 0e4e6d7094df ("crypto: hash - Count error stats differently")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>