batman-adv: Annotate functions with format strings

Signed-off-by: Sven Eckelmann <sven@narfation.org>

net/batman-adv/bat_debugfs.c

@@ -50,6 +50,7 @@ static void emit_log_char(struct debug_log *debug_log, char c)
 		debug_log->log_start = debug_log->log_end - log_buff_len;
 }
 
+__printf(2, 3)
 static int fdebug_log(struct debug_log *debug_log, char *fmt, ...)
 {
 	va_list args;

net/batman-adv/main.h

@@ -136,7 +136,7 @@ void dec_module_count(void);
 int is_my_mac(uint8_t *addr);
 
 #ifdef CONFIG_BATMAN_ADV_DEBUG
-int debug_log(struct bat_priv *bat_priv, char *fmt, ...);
+int debug_log(struct bat_priv *bat_priv, char *fmt, ...) __printf(2, 3);
 
 #define bat_dbg(type, bat_priv, fmt, arg...)			\
 	do {							\
@@ -145,6 +145,7 @@ int debug_log(struct bat_priv *bat_priv, char *fmt, ...);
 	}							\
 	while (0)
 #else /* !CONFIG_BATMAN_ADV_DEBUG */
+__printf(3, 4)
 static inline void bat_dbg(char type __always_unused,
 			   struct bat_priv *bat_priv __always_unused,
 			   char *fmt __always_unused, ...)