asoc: wcd: acquire wakelock during cable detection

There could be race condition that suspend is called
even before the detection is completed which can
result in high power numbers. Make sure device doesn't
go to suspend until the detection logic is completed.

Change-Id: I38d049b020137562aa4b5cb7c335781b3d4ada16
Signed-off-by: Simmi Pateriya <simmip@codeaurora.org>