[CRYPTO] scatterwalk: Use generic scatterlist chaining

This patch converts the crypto scatterwalk code to use the generic
scatterlist chaining rather the version specific to crypto.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/crypto/hmac.c b/crypto/hmac.c
index 0f05be7..34c3706 100644
--- a/crypto/hmac.c
+++ b/crypto/hmac.c
@@ -160,7 +160,7 @@
 
 	sg_init_table(sg1, 2);
 	sg_set_buf(sg1, ipad, bs);
-	sg_set_page(&sg1[1], (void *) sg, 0, 0);
+	sg_chain(sg1, 2, sg);
 
 	sg_init_table(sg2, 1);
 	sg_set_buf(sg2, opad, bs + ds);