[libsanitizer] Define SANITIZER_IOS when building for iOS or iOS simulator.
Do not use struct stat64 and struct statfs64 when building for iOS, where __DARWIN_ONLY_64_BIT_INO_T is set to 1.




git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@193775 91177308-0d34-0410-b5e6-96231b3b80d8