crypto: marvell/cesa - factor out first fragment decisions to helper

Multiple locations in the driver test the operation context fragment
type, checking whether it is a first fragment or not.  Introduce a
mv_cesa_mac_op_is_first_frag() helper, which returns true if the
fragment operation is for a first fragment.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/drivers/crypto/marvell/cesa.h b/drivers/crypto/marvell/cesa.h
index 14f8285..1103405 100644
--- a/drivers/crypto/marvell/cesa.h
+++ b/drivers/crypto/marvell/cesa.h
@@ -686,6 +686,12 @@
 	return engine->int_mask;
 }
 
+static inline bool mv_cesa_mac_op_is_first_frag(const struct mv_cesa_op_ctx *op)
+{
+	return (mv_cesa_get_op_cfg(op) & CESA_SA_DESC_CFG_FRAG_MSK) ==
+		CESA_SA_DESC_CFG_FIRST_FRAG;
+}
+
 int mv_cesa_queue_req(struct crypto_async_request *req);
 
 /* TDMA functions */