[tsan] use our own GetEnv instead of libc's getenv

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@175498 91177308-0d34-0410-b5e6-96231b3b80d8
[sanitizer] Add interceptors for localtime and friends.


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@175499 91177308-0d34-0410-b5e6-96231b3b80d8