common: Implement size matching on screen-integrated devices

On these devices, attempt to find a match based on device WxH calculations
and output size information from EDID. Allow for a certain error threshold
as sizes don't exactly match.

https://bugzilla.gnome.org/show_bug.cgi?id=730583
common: Removed hard-coded device name/edid mapping

This is generally too flaky (mismatches between display vendors
and touch manufacturers, changes between hardware model revisions...),
and size matching proves alright for the only model handled there.
sm