Add doxygen comments for MB_MODE_INFO

Change-Id: I611581c6b686beeb89766d49dac230f1c25ef468
diff --git a/av1/decoder/inspection.h b/av1/decoder/inspection.h
index b963f6a..70b1c80 100644
--- a/av1/decoder/inspection.h
+++ b/av1/decoder/inspection.h
@@ -38,7 +38,7 @@
   int16_t ref_frame[2];
   int16_t mode;
   int16_t uv_mode;
-  int16_t sb_type;
+  int16_t bsize;
   int16_t skip;
   int16_t segment_id;
   int16_t dual_filter_type;