Input: ALPS - move pixel and bitmap info into alps_data struct

Newer touchpads use different constants, so make them runtime-
configurable.

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Tested-by: Dave Turvene <dturvene@dahetral.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>