DW xGMAC IP can be synthesized such that it can support tx checksum
offloading only for a few initial tx queues. Also as Serge pointed
out, for the DW QoS IP, tx coe can be individually configured for
each tx queue. This patchset adds support for tx coe sw fallback for
those queues that don't support tx coe. Also, add binding for
snps,coe-unsupported property.