mlxsw: Implement ethtool operation to write to a transceiver module EEPROM

Implement the ethtool_ops::set_module_eeprom_by_page operation to allow
ethtool to write to a transceiver module EEPROM, in a similar fashion to
the ethtool_ops::get_module_eeprom_by_page operation.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>