HID: multitouch: remove last usb dependency

hid-multitouch used to direclty call for a set_idle in the .resume()
callback. With the new hid_hw_idle(), this can be dropped and
hid-multitouch is now freed from its transport layer.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>