tsan: refactor deadlock detector
Introduce DDetector interface between the tool and the DD itself.
It will help to experiment with other DD implementation,
as well as reuse DD in other tools.



git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@202485 91177308-0d34-0410-b5e6-96231b3b80d8