msm: perf: clean up duplicate constraint events

Events with a duplicate constraint are set to state=OFF when detected,
so that their duplicate counts are not read. However, they were not being
cleaned up because the core code only cleaned up ACTIVE events.
This resulted in counters not being freed and eventually running out
of resources.

Clean up the events with state==OFF that were marked that way because of
constraint duplication.
Ensure counts are not updated for OFF events.

Change-Id: If532801c79e6ad6809869eb0a3063774f00c92c3
Signed-off-by: Neil Leeder <nleeder@codeaurora.org>