Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/gpio/gpio-exar.c b/drivers/gpio/gpio-exar.c
index 0ecd236..fae327d 100644
--- a/drivers/gpio/gpio-exar.c
+++ b/drivers/gpio/gpio-exar.c
@@ -1,11 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * GPIO driver for Exar XR17V35X chip
  *
  * Copyright (C) 2015 Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
  */
 #include <linux/bitops.h>
 #include <linux/device.h>
@@ -148,6 +145,8 @@
 	mutex_init(&exar_gpio->lock);
 
 	index = ida_simple_get(&ida_index, 0, 0, GFP_KERNEL);
+	if (index < 0)
+		goto err_destroy;
 
 	sprintf(exar_gpio->name, "exar_gpio%d", index);
 	exar_gpio->gpio_chip.label = exar_gpio->name;