Add OpenBSD 3.1 i386 to supported platforms (was: RC1?)

Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Too low processes-per-user limit, likely.

Yes, ofcourse...
This is what happens when you're in a hurry and tries to make everything
happen at the same time :)

Now it all passes:

OpenBSD 3.1 i386

./configure \ --with-perl            \ --enable-odbc          \ --with-CXX

All 89 tests passed.
Installation and some small testing seems to work just fine.

Magnus