Correct guard macros in header files

Change-Id: Ifce12a95c1cdc36dc6ac5a72759249a17407da9e
diff --git a/vp10/encoder/mbgraph.h b/vp10/encoder/mbgraph.h
index dda820b..f116dd7 100644
--- a/vp10/encoder/mbgraph.h
+++ b/vp10/encoder/mbgraph.h
@@ -8,8 +8,8 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#ifndef VP9_ENCODER_VP9_MBGRAPH_H_
-#define VP9_ENCODER_VP9_MBGRAPH_H_
+#ifndef VP10_ENCODER_MBGRAPH_H_
+#define VP10_ENCODER_MBGRAPH_H_
 
 #ifdef __cplusplus
 extern "C" {
@@ -37,4 +37,4 @@
 }  // extern "C"
 #endif
 
-#endif  // VP9_ENCODER_VP9_MBGRAPH_H_
+#endif  // VP10_ENCODER_MBGRAPH_H_