ASoC: WCD9310: Add 5ms delay during slimbus port shutdown

It is found that audio playback on wcd9304 CODEC is very
unstable after moving to shared data channel architecture.
Audio playback is muted due to continous overflow error from
SLIMBUS RX port. Adding 5ms delay between port disconnect and
deactivation of data channel to stablize audio playback.

Change-Id: Iba8fbb7b35ba183a560b25cee89f670cbef95302
Signed-off-by: Bharath Ramachandramurthy <bramacha@codeaurora.org>