mac80211: Use a cfg80211_chan_def in ieee80211_hw_conf_chan

Drivers that don't use chanctxes cannot perform VHT association because
they still use a "backward compatibility" pair of {ieee80211_channel,
nl80211_channel_type} in ieee80211_conf and ieee80211_local.

Signed-off-by: Karl Beldan <karl.beldan@rivierawaves.com>
[fix kernel-doc]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/drivers/net/wireless/rt2x00/rt61pci.c b/drivers/net/wireless/rt2x00/rt61pci.c
index f95792c..f85035c 100644
--- a/drivers/net/wireless/rt2x00/rt61pci.c
+++ b/drivers/net/wireless/rt2x00/rt61pci.c
@@ -847,7 +847,7 @@
 	u16 eeprom;
 	short lna_gain = 0;
 
-	if (libconf->conf->channel->band == IEEE80211_BAND_2GHZ) {
+	if (libconf->conf->chandef.chan->band == IEEE80211_BAND_2GHZ) {
 		if (test_bit(CAPABILITY_EXTERNAL_LNA_BG, &rt2x00dev->cap_flags))
 			lna_gain += 14;