mt76: unify set_tim

All mt76 drivers (now also USB drivers) require empty .set_tim
callback. Add it to common mt76 module and use on all drivers.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mac80211.c

@@ -789,3 +789,10 @@ void mt76_csa_check(struct mt76_dev *dev)
 		__mt76_csa_check, dev);
 }
 EXPORT_SYMBOL_GPL(mt76_csa_check);
+
+int
+mt76_set_tim(struct ieee80211_hw *hw, struct ieee80211_sta *sta, bool set)
+{
+	return 0;
+}
+EXPORT_SYMBOL_GPL(mt76_set_tim);