wifi: cfg80211: add ieee80211_chanwidth_rate_flags()

To simplify things when we don't have a full chandef,
add ieee80211_chanwidth_rate_flags().
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

include/net/cfg80211.h

@@ -939,19 +939,18 @@ int cfg80211_chandef_dfs_required(struct wiphy *wiphy,
 				  enum nl80211_iftype iftype);
 
 /**
- * ieee80211_chandef_rate_flags - returns rate flags for a channel
+ * ieee80211_chanwidth_rate_flags - return rate flags for channel width
+ * @width: the channel width of the channel
  *
  * In some channel types, not all rates may be used - for example CCK
  * rates may not be used in 5/10 MHz channels.
  *
- * @chandef: channel definition for the channel
- *
- * Returns: rate flags which apply for this channel
+ * Returns: rate flags which apply for this channel width
  */
 static inline enum ieee80211_rate_flags
-ieee80211_chandef_rate_flags(struct cfg80211_chan_def *chandef)
+ieee80211_chanwidth_rate_flags(enum nl80211_chan_width width)
 {
-	switch (chandef->width) {
+	switch (width) {
 	case NL80211_CHAN_WIDTH_5:
 		return IEEE80211_RATE_SUPPORTS_5MHZ;
 	case NL80211_CHAN_WIDTH_10:
@@ -962,6 +961,20 @@ ieee80211_chandef_rate_flags(struct cfg80211_chan_def *chandef)
 	return 0;
 }
 
+/**
+ * ieee80211_chandef_rate_flags - returns rate flags for a channel
+ * @chandef: channel definition for the channel
+ *
+ * See ieee80211_chanwidth_rate_flags().
+ *
+ * Returns: rate flags which apply for this channel
+ */
+static inline enum ieee80211_rate_flags
+ieee80211_chandef_rate_flags(struct cfg80211_chan_def *chandef)
+{
+	return ieee80211_chanwidth_rate_flags(chandef->width);
+}
+
 /**
  * ieee80211_chandef_max_power - maximum transmission power for the chandef
  *