Input: synaptics-rmi4 - fix axis-swap behavior

The documentation for the touchscreen-swapped-x-y property states that
swapping is done after inverting if both are used. RMI4 did it the other
way around, leading to inconsistent behavior with regard to other
touchscreens.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Tested-by: Nick Dyer <nick@shmanahar.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>