[TSan] Makefiles: allow configurable paths to clang and FileCheck. Add -fno-rtti flag.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@177247 91177308-0d34-0410-b5e6-96231b3b80d8
[TSan] Use ThreadRegistry::FindThreadContextLocked() to find thread by its stack/tls address.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@177248 91177308-0d34-0410-b5e6-96231b3b80d8
[TSan] fix undefined variable in debug TSan build

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@177249 91177308-0d34-0410-b5e6-96231b3b80d8
tsan: fix lint warnings


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@177251 91177308-0d34-0410-b5e6-96231b3b80d8