net: macb: Specify PHY PM management done by MAC

The `macb_resume`/`macb_suspend` methods already call the
`phylink_start`/`phylink_stop` methods during their execution so
explicitly say that the PM of the PHY is done by MAC by using the
`mac_managed_pm` flag of the `struct phylink_config`.

This also fixes the warning message issued during resume:
WARNING: CPU: 0 PID: 237 at drivers/net/phy/phy_device.c:323 mdio_bus_phy_resume+0x144/0x148

Depends-on: 96de900a ("net: phylink: add mac_managed_pm in phylink_config structure")
Fixes: 744d23c7 ("net: phy: Warn about incorrect mdio_bus_phy_resume() state")
Signed-off-by: Sergiu Moga <sergiu.moga@microchip.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/20221019120929.63098-1-sergiu.moga@microchip.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>