net: marvell: prestera: Implement initial inetaddr notifiers

Add inetaddr notifiers to support add/del IPv4 address on switchdev
port. We create TRAP on first address, added on port and delete TRAP,
when last address removed.
Currently, driver supports only regular port to became routed.
Other port type support will be added later

Co-developed-by: Taras Chornyi <tchornyi@marvell.com>
Signed-off-by: Taras Chornyi <tchornyi@marvell.com>
Co-developed-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>