Input: uinput - allow for max == min during input_absinfo validation

These values are inclusive, so a range of 1 requires min == max.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Martin Kepplinger <martin.kepplinger@ginzinger.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>