mac80211: Support multiple VIFS per AP in debugfs.

Create 'stations' sub-directory under each netdev:[vif-name]
directory to hold all stations for that network device.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/debugfs_netdev.c b/net/mac80211/debugfs_netdev.c
index 20b2998..3e124305 100644
--- a/net/mac80211/debugfs_netdev.c
+++ b/net/mac80211/debugfs_netdev.c
@@ -409,6 +409,9 @@
 	sprintf(buf, "netdev:%s", sdata->name);
 	sdata->debugfs.dir = debugfs_create_dir(buf,
 		sdata->local->hw.wiphy->debugfsdir);
+	if (sdata->debugfs.dir)
+		sdata->debugfs.subdir_stations = debugfs_create_dir("stations",
+			sdata->debugfs.dir);
 	add_files(sdata);
 }