Removing dpkg arch definitions for kopensolaris-any?

Hi!

Was checking the status of several of the dpkg arch definitions, and
whether they are in use and/or useful, and stumbled over the
kopensolaris-any ones.

These were requested in #509312. And I notice that the glibc ports
at both:

  <https://github.com/dtbartle/glibc-opensolaris>
  <https://github.com/ip1981/kopensolaris-glibc>

are not very lively. Are these being used anywhere? I don't think Dyson
for example is using glibc, and the port uses illumos as part of its
arch name anyway? If this is being used at all, I have no problem with
keeping this, the definition just seemed somewhat dead/unused to me.

(BTW dpkg from git HEAD now should build and pass all tests on current
Solaris/illumos. :)

Thanks,
Guillem