HID: logitech: Add support for Logitech G11 extra keys

The Logitech G11 keyboard is a cheap variant of the G15 without the LCD
screen. It uses the same layout for its extra and macro keys (G1 - G18,
M1-M3, MR) and - from the input subsystem's perspective - behaves just
like the G15, so we can treat it as such.

Tested it with my own keyboard.

Signed-off-by: Fabian Schindlatz <fabian.schindlatz@fau.de>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>