ASoC: sgtl5000: Disable internal PLL early

To handle the soft reboot case, the internal PLL must be
disabled in SGTL5000_CHIP_CLK_CTRL before clearing bits
SGTL5000_VCOAMP_POWERUP and SGTL5000_PLL_POWERUP in
register SGTL5000_CHIP_ANA_POWER.

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>