pkgsrc cross-compilation and other miscellaneous patches

[Taylor R Campbell <campbell+netbsd-tech-pkg%mumble.net@localhost>]

(I am not subscribed to this list, so please cc me in replies.)

I've brushed off the pile of patches I've been sitting on for ages to
do pkgsrc cross-compilation as discussed the other week, and a few
other little patches, and put them up at

   <http://www.NetBSD.org/~riastradh/tmp/pkgsrc-2013423>

Patches for cross-compilation are under cross/; patches to fix cross-
builds of various packages are under cross/packages/.

Instructions for users on how to set up cross-compilation are in
cross/howto-use-cross.txt; instructions for developers on how to make
packages cross-compile are in cross/howto-dev-cross.txt.

Each patch has a summary at the top which might serve as a commit
message.  The patches that have `XXX' in their first line are probably
not fit to commit, but I'd like to commit the rest.  Please review and
tell me everything that I've done horribly wrong!

(Also, let me know if I ought to submit PRs for some of the patches
instead of sitting on them or asking for review on tech-pkg.)