HID: multitouch: cleanup eGalax quirks

The previous implementation of eGalax protocol was not satisfying as
we had to manually set x/y ranges as they were corrupted after reading
the report descriptor.
Indeed, the report descriptor provided a stylus input interface which
override the correct values.

This patch omits this input, thus leaving the correct value untouched,
and the MT_QUIRK_EGALAX_XYZ_FIXUP not required anymore.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@enac.fr>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>