ASoC: tlv320aic31xx: Switch GPIO handling to use gpiod_* API

Move to using newer gpiod_* GPIO handling functions. This simplifies
the code and eases dropping platform data in the next patch. Also
remember GPIO are active low, so set "1" to reset.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>