Add #include <iostream> since Value.h does not #include it any more.

llvm-svn: 14622
diff --git a/llvm/lib/CodeGen/MachineInstr.cpp b/llvm/lib/CodeGen/MachineInstr.cpp
index 3f7e713..8a61849 100644
--- a/llvm/lib/CodeGen/MachineInstr.cpp
+++ b/llvm/lib/CodeGen/MachineInstr.cpp
@@ -21,6 +21,8 @@
 #include "llvm/Target/TargetInstrInfo.h"
 #include "llvm/Target/MRegisterInfo.h"
 #include "Support/LeakDetector.h"
+#include <iostream>
+
 using namespace llvm;
 
 // Global variable holding an array of descriptors for machine instructions.