Input: bu21013_ts - move GPIO init and exit functions into the driver

These GPIO init and exit functions have no place in platform data, they
should be part of the driver instead,

Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>