mac80211: constify IE parsing

Make all the parsed IE pointers const, and propagate
the change to all the users etc.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/mac80211/mesh_pathtbl.c b/net/mac80211/mesh_pathtbl.c
index d5786c3..2ce4c40 100644
--- a/net/mac80211/mesh_pathtbl.c
+++ b/net/mac80211/mesh_pathtbl.c
@@ -181,7 +181,7 @@
 	return -ENOMEM;
 }
 
-static u32 mesh_table_hash(u8 *addr, struct ieee80211_sub_if_data *sdata,
+static u32 mesh_table_hash(const u8 *addr, struct ieee80211_sub_if_data *sdata,
 			   struct mesh_table *tbl)
 {
 	/* Use last four bytes of hw addr and interface index as hash index */
@@ -326,8 +326,8 @@
 }
 
 
-static struct mesh_path *mpath_lookup(struct mesh_table *tbl, u8 *dst,
-					  struct ieee80211_sub_if_data *sdata)
+static struct mesh_path *mpath_lookup(struct mesh_table *tbl, const u8 *dst,
+				      struct ieee80211_sub_if_data *sdata)
 {
 	struct mesh_path *mpath;
 	struct hlist_node *n;
@@ -359,7 +359,8 @@
  *
  * Locking: must be called within a read rcu section.
  */
-struct mesh_path *mesh_path_lookup(u8 *dst, struct ieee80211_sub_if_data *sdata)
+struct mesh_path *mesh_path_lookup(const u8 *dst,
+				   struct ieee80211_sub_if_data *sdata)
 {
 	return mpath_lookup(rcu_dereference(mesh_paths), dst, sdata);
 }
@@ -494,7 +495,7 @@
  *
  * State: the initial state of the new path is set to 0
  */
-int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata)
+int mesh_path_add(const u8 *dst, struct ieee80211_sub_if_data *sdata)
 {
 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 	struct ieee80211_local *local = sdata->local;