Input: synaptics - set resolution for MT_POSITION_X/Y axes

Set resolution for MT_POSITION_X and MT_POSITION_Y to match ABS_X and
ABS_Y, respectively.

Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Acked-by: Chase Douglas <chase.douglas@canonical.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>