mac80211: Fix addition of mesh configuration element

The code was setting the capabilities byte to zero,
after it was already properly set previously. Fix it.

The bug was found while debugging hwsim mesh tests failures
that happened since the commit mentioned below.

Fixes: 76f43b4c0a93 ("mac80211: Remove invalid flag operations in mesh TSF synchronization")
Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Reviewed-by: Masashi Honma <masashi.honma@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/mesh.c

@@ -279,8 +279,6 @@ int mesh_add_meshconf_ie(struct ieee80211_sub_if_data *sdata,
 	/* Mesh PS mode. See IEEE802.11-2012 8.4.2.100.8 */
 	*pos |= ifmsh->ps_peers_deep_sleep ?
 			IEEE80211_MESHCONF_CAPAB_POWER_SAVE_LEVEL : 0x00;
-	*pos++ = 0x00;
-
 	return 0;
 }