batman-adv: use DBG_ALL in log_level sysfs definition

Each time a new log level is added the developer must change either the DBG_ALL
enum definition and the hard coded value in the bat_sysfs.c for the log_level
attribute max value. This is extremely error prone.
With this patch the code directly uses DBG_ALL in the sysfs definition
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>

net/batman-adv/bat_sysfs.c

@@ -445,7 +445,7 @@ BAT_ATTR_SIF_UINT(gw_sel_class, S_IRUGO | S_IWUSR, 1, TQ_MAX_VALUE,
 static BAT_ATTR(gw_bandwidth, S_IRUGO | S_IWUSR, show_gw_bwidth,
 		store_gw_bwidth);
 #ifdef CONFIG_BATMAN_ADV_DEBUG
-BAT_ATTR_SIF_UINT(log_level, S_IRUGO | S_IWUSR, 0, 15, NULL);
+BAT_ATTR_SIF_UINT(log_level, S_IRUGO | S_IWUSR, 0, DBG_ALL, NULL);
 #endif
 
 static struct bat_attribute *mesh_attrs[] = {