Add support for the four-port variant of the Qualcomm QCA833x switch.
Signed-off-by: Michal Vokáč <michal.vokac@ysoft.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>