ASoC: wcd: disable PA when headset is removed

When headset is removed during playback, it takes
~3 secs for PA to be disabled. If again headset is
inserted within this time, it can cause wrong
detection issues, as we use HPHL/HPHR schmitt triggers
to check cross connection. Results of HPHL/HPHR
schmitt triggers are not reliable when PA's are on.

CRs-Fixed: 653658
Change-Id: Ifcad2109403324a084f925496baac67ffe40c342
Signed-off-by: Simmi Pateriya <simmip@codeaurora.org>