HID: support for Kensington slimblade device

0x47d/0x2041 device sends two extra buttons in 0xff00 usage
page and therefore requires special handling.

Reported-by: Jason Noble <nobleja@polezero.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
index 0fdbda6..53e1331 100644
--- a/drivers/hid/Makefile
+++ b/drivers/hid/Makefile
@@ -29,6 +29,7 @@
 obj-$(CONFIG_DRAGONRISE_FF)	+= hid-drff.o
 obj-$(CONFIG_HID_EZKEY)		+= hid-ezkey.o
 obj-$(CONFIG_HID_GYRATION)	+= hid-gyration.o
+obj-$(CONFIG_HID_KENSINGTON)	+= hid-kensington.o
 obj-$(CONFIG_HID_LOGITECH)	+= hid-logitech.o
 obj-$(CONFIG_HID_MICROSOFT)	+= hid-microsoft.o
 obj-$(CONFIG_HID_MONTEREY)	+= hid-monterey.o