msm: mdss: hdmi: update audio and avmute based on encryption level

Update audio routing based on minimum encryption level requirements.
In case current HDCP status is different than what is required, do not
switch audio to sink and set avmute. If required level is minimum,
route audio to sink and unset avmute.

Change-Id: Icef9d4901682d774c3ace95c6dbe6b8fe67eac0f
Signed-off-by: Ajay Singh Parmar <aparmar@codeaurora.org>