Purge unused includes throughout libSupport.

NFC.

llvm-svn: 232976
diff --git a/llvm/lib/Support/Unix/Program.inc b/llvm/lib/Support/Unix/Program.inc
index baf2767..5816fb8 100644
--- a/llvm/lib/Support/Unix/Program.inc
+++ b/llvm/lib/Support/Unix/Program.inc
@@ -18,10 +18,11 @@
 
 #include "Unix.h"
 #include "llvm/ADT/StringExtras.h"
+#include "llvm/Config/config.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/FileSystem.h"
+#include "llvm/Support/Path.h"
 #include "llvm/Support/raw_ostream.h"
-#include <llvm/Config/config.h>
 #if HAVE_SYS_STAT_H
 #include <sys/stat.h>
 #endif