drivers: gpio: remove duplicate includes

These duplicate includes have been found with scripts/checkincludes.pl
but they have been removed manually to avoid removing false positives.

Signed-off-by: Pravin Shedge <pravin.shedge4linux@gmail.com>
Acked-by: Gregory Fong <gregory.0xf0@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>