ASoC: codecs: ad193x: Fix memory corruption on BE 64b systems

Since change_bit() requires unsigned long*, making this cast on an
unsigned int variable will change a wrong bit on BE platforms, causing
memory corruption. Replace this function with a simple XOR.

Fixes: 90f6e680 ("ASoC: codecs: ad193x: Fix frame polarity for DSP_A format")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
Signed-off-by: Mark Brown <broonie@kernel.org>