net: smsc911x: Stop and start PHY during suspend and resume

Commit 744d23c7 ("net: phy: Warn about incorrect
mdio_bus_phy_resume() state") unveiled that the smsc911x driver was not
properly stopping and restarting the PHY during suspend/resume. Correct
that by indicating that the MAC is in charge of PHY PM operations and
ensure that all MDIO bus activity is quiescent during suspend.

Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Fixes: fba863b8 ("net: phy: make PHY PM ops a no-op if MAC driver manages PHY PM")
Fixes: 2aa70f86 ("net: smsc911x: Quieten netif during suspend")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20220825023951.3220-1-f.fainelli@gmail.com


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