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/lz4.c b/crypto/lz4.c
index 34d072b..aefbcea 100644
--- a/crypto/lz4.c
+++ b/crypto/lz4.c
@@ -104,3 +104,4 @@
 
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("LZ4 Compression Algorithm");
+MODULE_ALIAS_CRYPTO("lz4");