Input: add KEY_SPELLCHECK

HUT 1.12 defines Spell Check usage 0x1ab in Consumer page. There are
keyboards out there emitting this usage code (for example Microsoft
Natural Ergonomic Keyboard 4000). Add this key so that HID code could
map usages to it.
Acked-by: NDmitry Torokhov <dtor@mail.ru>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

include/linux/input.h

@@ -523,6 +523,7 @@ struct input_absinfo {
 #define KEY_ADDRESSBOOK		0x1ad	/* AL Contacts/Address Book */
 #define KEY_MESSENGER		0x1ae	/* AL Instant Messaging */
 #define KEY_DISPLAYTOGGLE	0x1af	/* Turn display (LCD) on and off */
+#define KEY_SPELLCHECK		0x1b0   /* AL Spell Check */
 
 #define KEY_DEL_EOL		0x1c0
 #define KEY_DEL_EOS		0x1c1