ARM - shmobile: Armadillo800EVA: Move st1232 reset pin handling

We no longer need to set up the reset pin for the st1232 in the board
code, but can pass the GPIO number via the platform data to the driver.
This results in a cleaner grouping of the device setup.

Signed-off-by: Bastian Hecht <hechtb+renesas@gmail.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>