[CRYPTO] digest: Include internal.h for prototypes

Every file should include the headers containing the externs for its 
global code (in this case for struct crypto_{init,exit}_digest_ops()).

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/crypto/digest.c b/crypto/digest.c
index 6fd43bd..b526cc3 100644
--- a/crypto/digest.c
+++ b/crypto/digest.c
@@ -21,6 +21,8 @@
 #include <linux/module.h>
 #include <linux/scatterlist.h>
 
+#include "internal.h"
+
 static int init(struct hash_desc *desc)
 {
 	struct crypto_tfm *tfm = crypto_hash_tfm(desc->tfm);