eeepc-wmi: add additional hotkeys

Added 4 hotkeys using same keymap values as eeepc-latop.
These are mousepad toggle, resolution change, screen off,
and task manager.  These were tested on 1005PE and are the
Fn-F3, F4, F7, and F9, respectively.

Also, added a new hot key for power toggles (Fn-Space on 1005PE)
and is meant to drive cpufv interface from userspace.

Signed-off-by: Chris Bagwell <chris@cnpbagwell.com>
Signed-off-by: Matthew Garrett <mjg@redhat.com>