[msan] Intercept pthread_key_create.


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@185693 91177308-0d34-0410-b5e6-96231b3b80d8
[sanitizer] Fix mac build.


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@185706 91177308-0d34-0410-b5e6-96231b3b80d8