Fix OMPT event_barrer_end

The OMPT status is never equal to ompt_status_track. ompt_status_track = 0x2
and ompt_status_track_callback = 0x6 just share a bit, so that we can check
for traceing and callbacks with the same status.

Patch by Tim Cramer

Differential Revision: http://reviews.llvm.org/D10863