[tsan] Fix os_id of main thread

Currently, os_id of the main thread contains the PID instead of a thread ID. Let's fix this.

Differential Revision: https://reviews.llvm.org/D29106



git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@293201 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed