greybus: raw: Print expected/actual payload size on mismatch

Print (expected-payload-size actual-payload-size), when the size doesn't
match for requests received by the module. This gives more details
required for debugging the issue.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
diff --git a/drivers/staging/greybus/raw.c b/drivers/staging/greybus/raw.c
index 3be96db..a17a986 100644
--- a/drivers/staging/greybus/raw.c
+++ b/drivers/staging/greybus/raw.c
@@ -121,7 +121,8 @@
 
 	/* Verify size of payload */
 	if (op->request->payload_size < sizeof(*receive)) {
-		dev_err(raw->device, "raw receive request too small\n");
+		dev_err(raw->device, "raw receive request too small (%zu < %zu)\n",
+			op->request->payload_size, sizeof(*receive));
 		return -EINVAL;
 	}
 	receive = op->request->payload;