Revert "msm: mdss: hdmi: tear down audio at bootup if already started"

This reverts commit b591582c
("msm: mdss: hdmi: tear down audio at bootup if already started").
The programming sequence to tear down audio (as implemented on
MSM8994 platform) included directly writing to LPASS registers.
However, on 8996, TZ does not allow access to LPASS registers
from the APPS side.

Change-Id: I19c6c0d5f5019ea78463a2d0fbdbddd92edf7ab0
Signed-off-by: Tatenda Chipeperekwa <tatendac@codeaurora.org>