[CRYPTO] sha: Add module aliases for sha1 / sha256

Crypto modules should be loadable by their .cra_driver_name, so
we should make MODULE_ALIAS()es with these names. This patch adds
aliases for SHA1 and SHA256 only as that's what we need for
PadLock-SHA driver.

Signed-off-by: Michal Ludvig <michal@logix.cz>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>