gpio: gpio-tc3589x.c: fix checkpatch errors

Fix :
 gpio/gpio-tc3589x.c:285: ERROR: code indent should use tabs where possible
 gpio/gpio-tc3589x.c:286: ERROR: code indent should use tabs where possible
 gpio/gpio-tc3589x.c:287: ERROR: code indent should use tabs where possible
 gpio/gpio-tc3589x.c:347: ERROR: code indent should use tabs where possible

Signed-off-by: Laurent Navet <laurent.navet@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>