mac80211: dont use interface indices in drivers

This patch gets rid of the if_id stuff where possible in favour of
a new per-virtual-interface structure "struct ieee80211_vif". This
structure is located at the end of the per-interface structure and
contains a variable length driver-use data area.

This has two advantages:
 * removes the need to look up interfaces by if_id, this is better
   for working with network namespaces and performance
 * allows drivers to store and retrieve per-interface data without
   having to allocate own lists/hash tables

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/rtl8187_dev.c b/drivers/net/wireless/rtl8187_dev.c
index 8dab25a..0d71716 100644
--- a/drivers/net/wireless/rtl8187_dev.c
+++ b/drivers/net/wireless/rtl8187_dev.c
@@ -150,7 +150,8 @@
 		flags |= RTL8187_TX_FLAG_MORE_FRAG;
 	if (control->flags & IEEE80211_TXCTL_USE_RTS_CTS) {
 		flags |= RTL8187_TX_FLAG_RTS;
-		rts_dur = ieee80211_rts_duration(dev, priv->if_id, skb->len, control);
+		rts_dur = ieee80211_rts_duration(dev, priv->vif,
+						 skb->len, control);
 	}
 	if (control->flags & IEEE80211_TXCTL_USE_CTS_PROTECT)
 		flags |= RTL8187_TX_FLAG_CTS;
@@ -560,14 +561,13 @@
 	return 0;
 }
 
-static int rtl8187_config_interface(struct ieee80211_hw *dev, int if_id,
+static int rtl8187_config_interface(struct ieee80211_hw *dev,
+				    struct ieee80211_vif *vif,
 				    struct ieee80211_if_conf *conf)
 {
 	struct rtl8187_priv *priv = dev->priv;
 	int i;
 
-	priv->if_id = if_id;
-
 	for (i = 0; i < ETH_ALEN; i++)
 		rtl818x_iowrite8(priv, &priv->map->BSSID[i], conf->bssid[i]);