msm: mdss: Refactor deterministic frame rate control

There are multiple branch conditions in current FRC design,
Simplify its design using finite state machine structure since
it's actually following pre-defined behaviors in different
states. All supported states are defined in frc_fsm_states.

Change-Id: I3bb1af548dfcf97134f11602607698fc92c9fe51
Signed-off-by: Ray Zhang <rayz@codeaurora.org>