ionic: Update ionic_if.h with new extra port stats

ionic: Update ionic_if.h with new extra port stats

Add a new structure to report additional statistics from the firmware to
struct ionic_port_info. This new struct currently only contains FEC
related statistics, but any new port-level statistics collected by the
firmware would go into it.

The new structure is located in the same area as the unused
ionic_port_pb_stats structure, so this patch also removes that and its
supporting enumerations since they was never used in this driver.

Finally, to indicate firmware support for the new structure, introduce a
new device capability that the driver can use to see if the attached
device supports reporting these extra stats.

Signed-off-by: Eric Joyner <eric.joyner@amd.com>
Link: https://patch.msgid.link/20260614205303.48088-3-eric.joyner@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>