evdev: mask out MSC_TIMESTAMP, we don't need it

evdev: mask out MSC_TIMESTAMP, we don't need it

Not really an issue at this point, but some HID devices like sending
MSC_TIMESTAMP. Since we don't use them in libinput, all we do is drag
ourselves out of sleep, look at the event, frown because it's not our morning
coffee, and go back to sleep. Instead, disable the code altogether, libevdev
will mask it transparently and then the kernel will let us sleep.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>