Sofar far pktgen have had a restriction to only use one device per kernel
thread. With the new multiqueue architecture this is no longer adequate.
The patch below is an effort to remove this by in pktgen configuration
adding a tag to the device name a la eth0@0 etc. The tag is used for
usual device config just as before. Also a new flag is introduced to mirror
queue_map with sending threads smp_processor_id() QUEUE_MAP_CPU.
An example: We use 4 CPU's to send to one 10g interface (eth0)
and we use the new tagging to send a mix of packet sizes, 64, 576 and
1500 bytes. Also we use TX queues according to smp_processor_id()