soc: qcom: use interruptible wait_for_completion API

Device suspend fails because of un-interruptible blocking read
function. Use wait_for_completion_interruptible API instead of
wait_for_completion to allow device suspend.

Change-Id: Ia537e776d0b322d56cd6003f95cdded5e695ceeb
Signed-off-by: Vidyakumar Athota <vathota@codeaurora.org>