msm: mdss: hdmi: add dynamic fps support

Add dynamic fps support for hdmi to update the resolution
timings on the interface by either changing the clock rate
or by modifying the porch values or both. Dynamic fps feature
can by used for hdmi to support different use cases like
matching input stream fps with hdmi out.

Change-Id: Ia305e1eb5d3da1dfbf868650e5ee84018255476b
Signed-off-by: Ajay Singh Parmar <aparmar@codeaurora.org>