dpaa2-eth: Fix possible access beyond end of array

Make sure we don't try to enqueue XDP_REDIRECT frames to an
inexistent FQ.

While it is guaranteed not to have more than one queue per core,
having fewer queues than CPUs on an interface is a valid
configuration.

Fixes: d678be1d

 ("dpaa2-eth: add XDP_REDIRECT support")
Reported-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Ioana Radulescu <ruxandra.radulescu@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>