mt76: mt7615: fix possible deadlock while mt7615_register_ext_phy()

ieee80211_register_hw() is called with rtnl_lock held, and this could be
caused lockdep from a work item that's on a workqueue that is flushed
with the rtnl held.

Move mt7615_register_ext_phy() outside the init_work().
Signed-off-by: Peter Chiu <chui-hao.chiu@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mt7615/pci_init.c

@@ -28,8 +28,6 @@ static void mt7615_pci_init_work(struct work_struct *work)
 		return;
 
 	mt7615_init_work(dev);
-	if (dev->dbdc_support)
-		mt7615_register_ext_phy(dev);
 }
 
 static int mt7615_init_hardware(struct mt7615_dev *dev)
@@ -160,6 +158,12 @@ int mt7615_register_device(struct mt7615_dev *dev)
 	mt7615_init_txpower(dev, &dev->mphy.sband_2g.sband);
 	mt7615_init_txpower(dev, &dev->mphy.sband_5g.sband);
 
+	if (dev->dbdc_support) {
+		ret = mt7615_register_ext_phy(dev);
+		if (ret)
+			return ret;
+	}
+
 	return mt7615_init_debugfs(dev);
 }