ASoC: wcd9310: vote off runtime PM after disable SLIMBUS ports

If the vote for pm runtime is done while codec shutdown, it is possible
that the runtime pm vote occurs even before the slimbus port for tx/rx
audio channel is disconnected. This can cause problem in audio playback/
record. Fix by moving the vote for runtime pm after slimbus port has
been disconnected

Change-Id: I959a83be7bc381e80dfc0176c50cb60e59ce227b
Signed-off-by: Swaminathan Sathappan <Swami@codeaurora.org>
Signed-off-by: Patrick Lai <plai@codeaurora.org>