Input: add KEY_KBD_LAYOUT_NEXT

The HID usage tables define a key to cycle through a set of keyboard
layouts, let's add corresponding keycode.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

include/uapi/linux/input-event-codes.h

@@ -604,6 +604,7 @@
 #define KEY_SCREENSAVER		0x245	/* AL Screen Saver */
 #define KEY_VOICECOMMAND		0x246	/* Listening Voice Command */
 #define KEY_ASSISTANT		0x247	/* AL Context-aware desktop assistant */
+#define KEY_KBD_LAYOUT_NEXT	0x248	/* AC Next Keyboard Layout Select */
 
 #define KEY_BRIGHTNESS_MIN		0x250	/* Set Brightness to Minimum */
 #define KEY_BRIGHTNESS_MAX		0x251	/* Set Brightness to Maximum */