iwlwifi: mvm: add option that allows a vif to disable PS

We need to disable PS when a monitor vif is active or, in the future,
when a channel switch is happening.  Add a boolean to mvmvif that
allows PS to be disabled generically.  Additionally, make the monitor
interface use this new flag when it gets activated.

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
diff --git a/drivers/net/wireless/iwlwifi/mvm/mac80211.c b/drivers/net/wireless/iwlwifi/mvm/mac80211.c
index 531540c..98e14f9 100644
--- a/drivers/net/wireless/iwlwifi/mvm/mac80211.c
+++ b/drivers/net/wireless/iwlwifi/mvm/mac80211.c
@@ -2708,7 +2708,10 @@
 		ret = 0;
 		goto out;
 	case NL80211_IFTYPE_STATION:
+		break;
 	case NL80211_IFTYPE_MONITOR:
+		/* always disable PS when a monitor interface is active */
+		mvmvif->ps_disabled = true;
 		break;
 	default:
 		ret = -EINVAL;
@@ -2784,6 +2787,7 @@
 		goto out;
 	case NL80211_IFTYPE_MONITOR:
 		mvmvif->monitor_active = false;
+		mvmvif->ps_disabled = false;
 		break;
 	case NL80211_IFTYPE_AP:
 		/* This part is triggered only during CSA */