[sanitizer] fix the build on ancient gcc which has stricter rules about what can be put on TLS. Long term, we absolutely must build the run-times with the fresh target clang

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@169593 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed