msm: mdss: hdmi: fix 4k@60 scrambling issue

Enable scrambling for all the pixel clocks where scrambling is mandatory.

Also, do not process multiple interrupts of same HDMI cable status as
this can lead to spin multiple threads, one modifying scrambling data
while other accessing it, resulting in wrong interpretation of scrambling
related data.

Change-Id: I31f80315a7d1b70bc6a0a84f5cd2990021bb8025
Signed-off-by: Ajay Singh Parmar <aparmar@codeaurora.org>