ASoC: msm: Add hph gpio control for impedance detection

For headphone impedance detection, the switches controlling
the hifi amp enable need to be pulled high, otherwise
hph left and right impedance measurements are not accurate.
Add gpio control needed for headphone impedance detection.

Change-Id: I0df8fbdfb39bc954fe5c7d953791caeca46eefcf
Signed-off-by: Phani Kumar Uppalapati <phaniu@codeaurora.org>