Fix minor V3DfgPatternStats coding issues

src/CMakeLists.txt

@@ -64,6 +64,7 @@ set(HEADERS
     V3Dfg.h
     V3DfgOptimizer.h
     V3DfgPasses.h
+    V3DfgPatternStats.h
     V3DfgPeephole.h
     V3DfgVertices.h
     V3DupFinder.h

src/V3DfgPatternStats.h

@@ -14,10 +14,10 @@
 //
 //*************************************************************************
 
-#include "V3PchAstNoMT.h"
+#ifndef VERILATOR_V3DFGPATTERNSTATS_H_
+#define VERILATOR_V3DFGPATTERNSTATS_H_
 
 #include "V3Dfg.h"
-#include "V3DfgPasses.h"
 
 #include <algorithm>
 #include <map>
@@ -195,3 +195,5 @@ public:
         }
     }
 };
+
+#endif