gpio: mockup: Fix potential resource leakage when register a chip

If creation of software node fails, the locally allocated string
array is left unfreed. Free it on error path.

Fixes: 6fda593f ("gpio: mockup: Convert to use software nodes")
Cc: stable@vger.kernel.org
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

drivers/gpio/gpio-mockup.c

@@ -533,8 +533,10 @@ static int __init gpio_mockup_register_chip(int idx)
 	}
 
 	fwnode = fwnode_create_software_node(properties, NULL);
-	if (IS_ERR(fwnode))
+	if (IS_ERR(fwnode)) {
+		kfree_strarray(line_names, ngpio);
 		return PTR_ERR(fwnode);
+	}
 
 	pdevinfo.name = "gpio-mockup";
 	pdevinfo.id = idx;