Fix uninitialised CRIS insn

[Hans-Peter Nilsson]

> From: Alan Modra <amodra@gmail.com>
> Date: Mon, 16 Jun 2014 09:40:34 +0200

> > Thanks, though there are more.  For cris-elf, cris-linux and
> > mmix-knuth-mmixware, your changes has caused spurious extra
> > error messages.  (Please don't adjust the expected error
> > messsages to match; the bug is that the extra lines are
> > emitted.)
> 
> Yes, I know.  I mentioned that in a later message.

Oops, I missed that.

> I was hoping you'd deal with the testcase errors, rather than have
> me blundering around in your ports.

Ok, let's do that, thanks for your work.

brgds, H-P