crypto: sha1 - export sha1_update for reuse

Export the update function as crypto_sha1_update() to not have the need
to reimplement the same algorithm for each SHA-1 implementation. This
way the generic SHA-1 implementation can be used as fallback for other
implementations that fail to run under certain circumstances, like the
need for an FPU context while executing in IRQ context.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/include/crypto/sha.h b/include/crypto/sha.h
index 069e85b..83e6be5 100644
--- a/include/crypto/sha.h
+++ b/include/crypto/sha.h
@@ -82,4 +82,7 @@
 	u8 buf[SHA512_BLOCK_SIZE];
 };
 
+extern int crypto_sha1_update(struct shash_desc *desc, const u8 *data,
+			      unsigned int len);
+
 #endif