[cleanup] Remove some unused #ifdef's

This is all going through the VFS layer now, so there's nothing
platform-specific here.

llvm-svn: 239573

clang/lib/Basic/FileSystemStatCache.cpp

@@ -15,19 +15,8 @@
 #include "clang/Basic/VirtualFileSystem.h"
 #include "llvm/Support/Path.h"
 
-// FIXME: This is terrible, we need this for ::close.
-#if !defined(_MSC_VER) && !defined(__MINGW32__)
-#include <unistd.h>
-#include <sys/uio.h>
-#else
-#include <io.h>
-#endif
 using namespace clang;
 
-#if defined(_MSC_VER)
-#define S_ISDIR(s) ((_S_IFDIR & s) !=0)
-#endif
-
 void FileSystemStatCache::anchor() { }
 
 static void copyStatusToFileData(const vfs::Status &Status,