net/funeth: Support for ethtool -m

Add the FW command for reading port module memory pages and implement
ethtool's get_module_eeprom_by_page operation.

Signed-off-by: Dimitris Michailidis <dmichail@fungible.com>
Link: https://lore.kernel.org/r/20220627182000.8198-1-dmichail@fungible.com


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