devlink: Fix error message in devlink_rate_set_ops_supported()

The WARN_ON() macro takes a condition, it doesn't take a message.  Use
WARN() instead.

Fixes: 1897db2e ("devlink: Allow setting tx rate for devlink rate leaf objects")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/devlink.c

@@ -1732,7 +1732,7 @@ static bool devlink_rate_set_ops_supported(const struct devlink_ops *ops,
 			return false;
 		}
 	} else {
-		WARN_ON("Unknown type of rate object");
+		WARN(1, "Unknown type of rate object");
 		return false;
 	}