drm/msm/dp: add dp mst audio support

Implement audio support for dp mst mode. This change
registers/deregisters display interface with msm-ext-disp
module for each active stream with audio support. This
change also provides a new api to audio codec module to
update the ops for a selected codec based on the given
codec id information.

CRs-Fixed: 2192818
Change-Id: I26f3d39536f15cdf3be205f745accc6db59c03ef
Signed-off-by: Govinda Rajulu Chenna <gchenna@codeaurora.org>