msm: mdss: hdmi: Handle fast HPD interrupts

When downstream device cable is connected and disconnected
very quickly, or connect/disconnect processing takes more time
than expected, HPD state machine needs to be put into right state
to make sure HDMI is subsequently turned ON and OFF properly.

Change-Id: I96fbc454951b6bbf5af05b2b74a04f7ba4ddce11
Signed-off-by: Ajay Singh Parmar <aparmar@codeaurora.org>