give softnet threads unique names by suffixing softnet with their index.

give softnet threads unique names by suffixing softnet with their index.

ie, you'll see softnet0, softnet1, etc in top/ps/etc now instead
of just softnet on these threads.

this is done by wrapping the taskq and name up in a softnet struct.

ok patrick@ bluhm@ mvs@ kn@ sashan@