bnxt_en: Support force speed using the new HWRM fields

Modify bnxt_force_link_speed() to support the new speeds stored in
link_info->support_speeds2, including the new 400G speed.

Reviewed-by: Ajit Khaparde <ajit.khaparde@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Link: https://lore.kernel.org/r/20231201223924.26955-14-michael.chan@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>