Revert llvm-lto2 case

Author: arsenm

llvm/tools/llvm-lto2/llvm-lto2.cpp

@@ -25,6 +25,7 @@
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/InitLLVM.h"
+#include "llvm/Support/PluginLoader.h"
 #include "llvm/Support/TargetSelect.h"
 #include "llvm/Support/Threading.h"
 #include <atomic>