[CodeGen] Rename DEBUG_TYPE to match passnames

Rename missing DEBUG_TYPE "machine-scheduler" from backend files, which were
absent from https://reviews.llvm.org/rL303921.

Differential revision: https://reviews.llvm.org/D35231

llvm-svn: 307719
diff --git a/llvm/lib/CodeGen/MacroFusion.cpp b/llvm/lib/CodeGen/MacroFusion.cpp
index 5e279b0..633a853 100644
--- a/llvm/lib/CodeGen/MacroFusion.cpp
+++ b/llvm/lib/CodeGen/MacroFusion.cpp
@@ -24,7 +24,7 @@
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Target/TargetInstrInfo.h"
 
-#define DEBUG_TYPE "misched"
+#define DEBUG_TYPE "machine-scheduler"
 
 STATISTIC(NumFused, "Number of instr pairs fused");