ASoC: codecs: ad193x: Reset used registers at probe

Since the ad193x codecs have no software reset, we have to reinitialize the
registers after a hardware reset to assure no previous values are kept.

Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
Signed-off-by: Mark Brown <broonie@kernel.org>