78b04b54f8
Add support for i586-unknown-netbsd as target. This restricts instructions to those offered by Pentium, to support e.g. AMD Geode. There is already an entry for this target in the NetBSD platform support page at src/doc/rustc/src/platform-support/netbsd.md ...so this should forestall its removal. Additional fixes are needed for some vendored modules, this is the changes in the rust compiler core itself.