ASoC: tlv320aic31xx: Reset registers during power up

Add a reset function that toggles the reset line if available or uses
the software reset command otherwise. Use this in power up to ensure the
registers are in a sane state. This is useful when the driver module
is reloaded, or after Kexec, warm-reboots, etc..

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