Code style: Replace tab with space.
diff --git a/include/ndn-cpp/c/common.h b/include/ndn-cpp/c/common.h
index 7f47f7a..89392bc 100644
--- a/include/ndn-cpp/c/common.h
+++ b/include/ndn-cpp/c/common.h
@@ -5,7 +5,7 @@
  */
 
 #ifndef NDN_COMMON_H
-#define	NDN_COMMON_H
+#define NDN_COMMON_H
 
 #include "../ndn-cpp-config.h"
 #include <stdint.h>