smb-lib: wait before DRP for audio

The code currently switches to DRP immediately after a removal is
detected. This causes issues with audio since the mic bias remains enabled
and the user hears a pop noise.

Instead wait few milliseconds before switching to DRP, this way we allow
the audio driver to disable mic bias before switching to DRP.

Change-Id: Iec12bf5830b2aa487a475e10d795945064a346b1
Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>