msm: mdss: Support histogram v2

Add support for new histogram hardware that no longer needs to be reset
or kicked off. This changes the initial state we put the histogram
software into (no longer need to clear histogram data bins before
collecting, and now need to ensure hardware is unlocked), the way we
collect (no longer need to kickoff or enable auto-clear, and now need to
lock hardware while reading) and disable procedure (no longer need to
cancel potentially running histogram).

Since resets are now controlled by hardware (and operate on the buffer not
currently visible by software), we no longer need to track the status of
histogram reset requests.

Additionally, SSPP histogram no longer exists in v2, so prevent attempts
start, collect, or stop them.

Change-Id: I36be26c067481f306cf50d952334ba37e8deaaba
Signed-off-by: Carl Vanderlip <carlv@codeaurora.org>