ASoC: TWL4030: Use codec defaults for Headset initial configuration

Disable the amplifiers for the headset outputs, and do not select
routings by default to the headset outputs.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@nokia.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>