[sanitizer] one more stress test for the deadlock detector; this one stresses the slow path with a global lock

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@205299 91177308-0d34-0410-b5e6-96231b3b80d8
[TSan] Make this test more portable

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@205300 91177308-0d34-0410-b5e6-96231b3b80d8