Add 22.5 Gbps link rate definitions.

Link: https://lore.kernel.org/r/20211018070611.26428-1-sreekanth.reddy@broadcom.comReviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Sreekanth Reddy <sreekanth.reddy@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>