Input: synaptics-rmi4 - change F12 clip to inactive border debug

The data in F12_2D_Ctrl8 corresponds to the inactive border width used by
the RMI device. It is not in pixel units and should not be treated as a
clip value.

Signed-off-by: Nick Dyer <nick@shmanahar.org>
Tested-by: Chris Healy <cphealy@gmail.com>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>