kernel/gpio_keys: load module on pre-init

fix rescue mode on wdr4900

Backport of r48793

patches/openwrt/0045-kernel-gpio_keys-load-module-on-pre-init.patch

+From: Matthias Schiffer <mschiffer@universe-factory.net>
+Date: Sun, 28 Feb 2016 03:42:29 +0100
+Subject: kernel/gpio_keys: load module on pre-init
+
+fix rescue mode on wdr4900
+
+Backport of r48793
+
+diff --git a/package/kernel/linux/modules/input.mk b/package/kernel/linux/modules/input.mk
+index 86ff33c..eed9aa2 100644
+--- a/package/kernel/linux/modules/input.mk
++++ b/package/kernel/linux/modules/input.mk
+@@ -75,7 +75,7 @@ define KernelPackage/input-gpio-keys
+ 	CONFIG_KEYBOARD_GPIO \
+ 	CONFIG_INPUT_KEYBOARD=y
+   FILES:=$(LINUX_DIR)/drivers/input/keyboard/gpio_keys.ko
+-  AUTOLOAD:=$(call AutoProbe,gpio_keys)
++  AUTOLOAD:=$(call AutoProbe,gpio_keys,1)
+ endef
+ 
+ define KernelPackage/input-gpio-keys/description