net: sfp: use device_get_match_data()

Rather than using of_match_node() to get the matching of_device_id
to then retrieve the match data, use device_get_match_data() instead
to avoid firmware specific functions, and free the driver from having
firmware specific code.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>