of: unittest: Add of_node_put() before return

The local variable np in function of_unittest_platform_populate takes
the return value of of_find_node_by_path, which gets a node but does not
put it. If np is not put before return it may cause a memory leak. Hence
put np before a return statement.
Issue found with Coccinelle.

Signed-off-by: Nishka Dasgupta <nishkadg.linux@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>

drivers/of/unittest.c

@@ -1044,8 +1044,10 @@ static void __init of_unittest_platform_populate(void)
 	test_bus = platform_device_register_full(&test_bus_info);
 	rc = PTR_ERR_OR_ZERO(test_bus);
 	unittest(!rc, "testbus registration failed; rc=%i\n", rc);
-	if (rc)
+	if (rc) {
+		of_node_put(np);
 		return;
+	}
 	test_bus->dev.of_node = np;
 
 	/*