fixed comments in target link-layer address in NA to be consistent with RFC2461.  (no behavior change at the moment)
fixed comments in target link-layer address in NA to be consistent
with RFC2461.  (no behavior change at the moment)

MarginC/kame,MarginC/kame,MarginC/kame,MarginC/kame,MarginC/kame,MarginC/kame,MarginC/kame