msm: mdss: hdmi: fix hpd state machine on different use cases

Fix HPD (hot plug detect) state with respect to rest of the system
in different use cases like cable connect/disconnect, runtime
suspend/resume, PM suspend/resume, framework stop/start and sysfs
node hpd enable/disable. Set the switch nodes to correct states
in above cases. Protect event handler, sysfs node handler,  ISR
work with mutex as there can be race condition between PM events,
framework events and hardware interrupts.

Change-Id: I223602753985d7022a3394fc5f5821e6e36ab2cd
Signed-off-by: Ajay Singh Parmar <aparmar@codeaurora.org>