dpaa_eth: enable multiple Tx traffic classes

Implement the setup_tc ndo to configure prioritised Tx traffic classes.
Priorities range from 0 (lowest) to 3 (highest). The driver assigns
NR_CPUS queues to each traffic class.

Signed-off-by: Camelia Groza <camelia.groza@nxp.com>
Signed-off-by: Madalin Bucur <madalin.bucur@nxp.com>