rswitch: Fix imbalance phy_power_off() calling

The phy_power_off() should not be called if phy_power_on() failed.
So, add a condition .power_count before calls phy_power_off().

Fixes: 5cb6309 ("net: renesas: rswitch: Add phy_power_{on,off}() calling")
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

drivers/net/ethernet/renesas/rswitch.c

@@ -1254,7 +1254,7 @@ static void rswitch_adjust_link(struct net_device *ndev)
 		phy_print_status(phydev);
 		if (phydev->link)
 			phy_power_on(rdev->serdes);
-		else
+		else if (rdev->serdes->power_count)
 			phy_power_off(rdev->serdes);
 
 		rdev->etha->link = phydev->link;