crypto: api - Export crypto_alg_lookup instead of __crypto_alg_lookup

Since the only user of __crypto_alg_lookup is doing exactly what
crypto_alg_lookup does, we can now the latter in lieu of the former.

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

diff --cc crypto/algapi.c
Simple merge

diff --cc crypto/api.c
Simple merge

diff --cc crypto/internal.h
Simple merge