Input: gpio_tilt - delete driver

This driver was merged in 2011 as a tool for detecting the orientation
of a screen. The device driver assumes board file setup using the
platform data from <linux/input/gpio_tilt.h>. But no boards in the
kernel tree defines this platform data.

As I am faced with refactoring drivers to use GPIO descriptors and
pass decriptor tables from boards, or use the device tree device
drivers like these creates a serious problem: I cannot fix them and
cannot test them, not even compile-test them with a system actually
using it (no in-tree boardfile).

I suggest to delete this driver and rewrite it using device tree if
it is still in use on actively maintained systems.

I can also offer to rewrite it out of the blue using device tree if
someone promise to test it and help me iterate it.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Patchwork-Id: 10133609
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>