Scale up touch width and height values

The MT protocol expects width and height to be in sufrace units.
The values reported from the Intuos Pro appear to require scaling
by ~50x for my finger to produce reasonable values.
Declare ABS_X and ABS_Y for all device types

Devices capable of >2 touches were not declaring support for the ABS_X
and ABS_Y axes despite using pointer emulation. This does not appear
to be a problem under 3.7+ (where ABS_X and ABS_Y are somehow
declared elsewhere), but poses an issue for 2.6.38+ where the axes
are never declared (causing xf86-input-wacom to ignore it).