Since commit 744d23c71af39c7d ("net: phy: Warn about incorrect
mdio_bus_phy_resume() state"), a warning splat is printed during system
resume with Wake-on-LAN disabled:
WARNING: CPU: 0 PID: 626 at drivers/net/phy/phy_device.c:323 mdio_bus_phy_resume+0xbc/0xe4
As the Renesas SuperH Ethernet driver already calls phy_{stop,start}()
in its suspend/resume callbacks, it is sufficient to just mark the MAC
responsible for managing the power state of the PHY.
Fixes: fba863b816049b03 ("net: phy: make PHY PM ops a no-op if MAC driver manages PHY PM")
Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>