Follow up to r1875122: Actually fix (some of?) the crashes in Ruby.
* tools/dev/unix-build/Makefile.svn: Add more fixes I came up with while debugging Ruby crashes. Patches still relevant to current versions of Ruby (we're still on 2.4) have been submitted upstream. Also, re-create the ruby patch properly instead of appending to an existing patch file if already present.
* tools/dev/unix-build/Makefile.svn: Add patch for Ruby which will hopefully fix the bus errors we have been seeing on the svn-bb-openbsd buildbot. I haven't yet confirmed that this really fixes the issue but since the crash happens sporadically there is only one way to find out.
I have also found out that OpenBSD's port of Ruby disables the crashing code path on sparc64. Which is a bandaid, not a real fix since the problem could affect other platforms as well.