ASoC: msm8x16-wcd: update registers for IN1 and IN2 recording

Update codec driver to make micbias capless switch common
for IN1 to IN3. Update ANALOG_MICB_1_INT_RBIAS for IN2
appropriately at power down. Add support for speaker boost
mixer control.

CRs-Fixed: 641317
Change-Id: I65d8bcc4fde2f40264e21239d36ee4737c7a8c05
Signed-off-by: Aravind Kumar <akumark@codeaurora.org>