crypto: prefix module autoloading with "crypto-"

This prefixes all crypto module loading with "crypto-" so we never run
the risk of exposing module auto-loading to userspace via a crypto API,
as demonstrated by Mathias Krause:

https://lkml.org/lkml/2013/3/4/70

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/crypto/md5.c b/crypto/md5.c
index 7febeaa..36f5e5b 100644
--- a/crypto/md5.c
+++ b/crypto/md5.c
@@ -168,3 +168,4 @@
 
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("MD5 Message Digest Algorithm");
+MODULE_ALIAS_CRYPTO("md5");