cfg80211: free_priv for BSS info

When cfg80211 users have their own allocated data in the per-BSS
private data, they will need to free this when the BSS struct is
destroyed. Add a free_priv method and fix one place where the BSS
was kfree'd rather than released properly.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/wireless/scan.c b/net/wireless/scan.c
index 009d128..ec148f6 100644
--- a/net/wireless/scan.c
+++ b/net/wireless/scan.c
@@ -56,6 +56,8 @@
 	struct cfg80211_internal_bss *bss;
 
 	bss = container_of(ref, struct cfg80211_internal_bss, ref);
+	if (bss->pub.free_priv)
+		bss->pub.free_priv(&bss->pub);
 	kfree(bss);
 }