Add explicit #includes of <iostream>

llvm-svn: 25515
diff --git a/llvm/lib/CodeGen/RegAllocLinearScan.cpp b/llvm/lib/CodeGen/RegAllocLinearScan.cpp
index fbf6692..f5b081a 100644
--- a/llvm/lib/CodeGen/RegAllocLinearScan.cpp
+++ b/llvm/lib/CodeGen/RegAllocLinearScan.cpp
@@ -28,6 +28,7 @@
 #include "llvm/Support/Debug.h"
 #include <algorithm>
 #include <cmath>
+#include <iostream>
 #include <set>
 #include <queue>
 #include <memory>