iwlwifi: mvm: Advertise support for AP channel width change

The iwlmvm driver supports channel width change in AP mode.  Add the
proper flag.
Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>

drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c

@@ -624,6 +624,7 @@ int iwl_mvm_mac_setup_register(struct iwl_mvm *mvm)
 	hw->wiphy->features |= NL80211_FEATURE_P2P_GO_CTWIN |
 			       NL80211_FEATURE_LOW_PRIORITY_SCAN |
 			       NL80211_FEATURE_P2P_GO_OPPPS |
+			       NL80211_FEATURE_AP_MODE_CHAN_WIDTH_CHANGE |
 			       NL80211_FEATURE_DYNAMIC_SMPS |
 			       NL80211_FEATURE_STATIC_SMPS |
 			       NL80211_FEATURE_SUPPORTS_WMM_ADMISSION;