PATCH: mkfixinc.sh fixes

[Bruce Korb]

Laurynas Biveinis wrote:
> > Did you actually see a problem that this fixes?
> 
> Yes, did, because...
> 
> > If so, then please apply.  But no Linux triplet ought
> > to be matching any of the listed expressions at this
> > point, rendering this superfluous, yes?
> 
> ... if you check the section listing targets which avoid fixincluding,
> you'll see this triplet:
> *-*-gnu*.
> It matches blah-blah-linux-gnu. So we have to apply my fix or to remove
> that triplet from the list. IMHO the later, because *-*-gnu* is way too
> general - something more specific should be put there instead.

Yep.  General questions:

1.  Which set of platforms does not match *-*-linux* but does match
    *-*-gnu*?

2.  Should they be using the fixincludes, too?  (i.e., Should we clobber
    the "*-*-gnu*" exception as well as the linux one?)