corrected some wrong behavior of icmp6_reflect():   - the destination address of the returned packet was checked for source     address selection, but it should actually be the detination of the     original packet.   - we don't need the special consideration for the M_LOOP and link-local case     any more   - recovered the consideration for the case of sending an error that occurs     in an output path (it still doesn't work in some cases since icmp6_error()     do not have enough information on the scope zone.  this should be fixed     separately)
corrected some wrong behavior of icmp6_reflect():
  - the destination address of the returned packet was checked for source
    address selection, but it should actually be the detination of the
    original packet.
  - we don't need the special consideration for the M_LOOP and link-local case
    any more
  - recovered the consideration for the case of sending an error that occurs
    in an output path (it still doesn't work in some cases since icmp6_error()
    do not have enough information on the scope zone.  this should be fixed
    separately)

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