ASoC: sgtl5000: Initialize CHIP_ANA_POWER to power-on defaults

Initialize CHIP_ANA_POWER to match power on defaults, which disables
ADC, DAC, and charge pumps.

In the process, remove references to the following register/bitfields
from the sgtl5000_set_power_regs routine:
	CHIP_ANA_POWER/LINREG_SIMPLE_POWERUP and
	CHIP_LINREG_CTRL/LINREG_VDD_MASK

And remove CHIP_ANA_POWER and CHIP_LINREG_CTRL from the set of default
registers so they don't get clobbered by sgtl5000_fill_defaults().

Signed-off-by: Eric Nelson <eric@nelint.com>
Signed-off-by: Clemens Gruber <clemens.gruber@pqgruber.com>
Tested-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>