dev: add option to assign one rx and one tx queue per thread

dev: add option to assign one rx and one tx queue per thread

queue 0 -> main
queue 1 -> thread 1 (worker 0)
queue 2 -> thread 2 (worker 1)

etc...

example startup.conf entry:

devices {
  dev pci/0002:04:00.0 {
    port 0 {
      name eth2
      flags queue-per-thread
    }
  }
}

Type: improvement
Change-Id: Ia1c216905c5e4368a0e2e47688fd87348be20106
Signed-off-by: Damjan Marion <[email protected]>