net/mlx5e: Add ethtool support for dump module EEPROM

Add query MCIA, PMLP registers infrastructure and commands.
Add ethtool support for get_module_info() and get_module_eeprom()
callbacks.

Signed-off-by: Gal Pressman <galp@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>