extcon: arizona: Only set GPIO if it has been requested

The micd_pol GPIO is only requested if we've specified one greater than 0
so apply the same test before we set it.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Myungjoo Ham <myungjoo.ham@samsung.com>