tsan: do not crash when apparently bogus fd is passed to e.g. close

some tests test libc/filesystem error handling paths (e.g. close(INT_MAX)),
currently such tests fail
with this change they work as expected



git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@193400 91177308-0d34-0410-b5e6-96231b3b80d8