mac80211: enable hash table shrinking

The hashtable behaviour change was merged into the tree
at about the same time as the mac80211 use of rhashtable,
but of course these don't really conflict in the normal
sense. Enable hash table shrinking now.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/sta_info.c

@@ -66,6 +66,7 @@
 
 static const struct rhashtable_params sta_rht_params = {
 	.nelem_hint = 3, /* start small */
+	.automatic_shrinking = true,
 	.head_offset = offsetof(struct sta_info, hash_node),
 	.key_offset = offsetof(struct sta_info, sta.addr),
 	.key_len = ETH_ALEN,