guenther spotted my bad copy and pasting.

fall back to htobe64 for htobem64 instead of htole64 on LE archs.
Simplify the way divert(4) sends packets to userspace: Instead of
unnecessarily allocating an mbuf tag to store the divert port, just pass
the divert port directly to divert_packet() or divert6_packet() as an
argument.

includes a style fix pointed out by bluhm@
ok bluhm@ henning@ reyk@
divert-packet no longer uses the PACKET_TAG_PF_DIVERT mbuf tag.