batman-adv: use NO_FLAGS define instead of hard-coding 0

The definition NO_FLAGS was introduced to make the code more
readable and shall be used to initialize flag fields.

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
diff --git a/net/batman-adv/main.h b/net/batman-adv/main.h
index 27ad734..ed488cb 100644
--- a/net/batman-adv/main.h
+++ b/net/batman-adv/main.h
@@ -51,6 +51,8 @@
 #define TQ_LOCAL_BIDRECT_RECV_MINIMUM 1
 #define TQ_TOTAL_BIDRECT_LIMIT 1
 
+#define NO_FLAGS 0
+
 #define NUM_WORDS (TQ_LOCAL_WINDOW_SIZE / WORD_BIT_SIZE)
 
 #define LOG_BUF_LEN 8192	  /* has to be a power of 2 */