Udev Rule: enable wakeup from suspend on Unifying receivers

The Unifying receiver does not allow to resume from suspend just pressing a key of the keyboard or a button of the mouse, this is because it's not allowed to wakeup the system (at least in Ubuntu 14.04).

Setting the enabled bit on the wakeup usb sys-node make possible to resume
from suspend when using wireless keyboards and mice.

I've integrated the current udev rule, instead of doing a new one, not to duplicate the devices IDs checks.