net: phy: smsc: add WoL support to LAN8740/LAN8742 PHYs

net: phy: smsc: add WoL support to LAN8740/LAN8742 PHYs

Microchip LAN8740/LAN8742 PHYs support basic unicast, broadcast, and
Magic Packet WoL.  They have one pattern filter matching up to 128 bytes
of frame data, which can be used to implement ARP or multicast WoL.

ARP WoL matches any ARP frame with broadcast address.

Multicast WoL matches any multicast frame.

Signed-off-by: Tristram Ha <Tristram.Ha@microchip.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Link: https://lore.kernel.org/r/1690329270-2873-1-git-send-email-Tristram.Ha@microchip.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>