addition of pflog_if_print to the tcpdump code can break buildworld

The addition of pflog_if_print to the tcpdump code breaks buildworld if
WITHOUT_PF= is set in /etc/src.conf.

I do not use PF and have WITHOUT_PF= set in /etc/src.conf.

If I comment out WITHOUT_PF= buildworld succeeds.  But I have no use for
PF and don't want to build it.

Here's the error code emitted when WITHOUT_PF= is defined:

ld: error: undefined symbol: pflog_if_print
>>> referenced by print.c
>>>               print.o:(printers)
>>> did you mean: nflog_if_print
>>> defined in: print-nflog.o
cc: error: linker command failed with exit code 1 (use -v to see invocation)
*** [tcpdump] Error code 1

If all else fails the WITHOUT_PF option should be removed, if a fix in
tcpdump isn't possible.

--
Gary Jennejohn