[RFA/mips] 128-bit long doubles for N32/N64

[Michael Chastain]

Andrew Cagney writes:
ac> I prefer to see us fix the problems, or at least 
ac> make it clear to the user that the feature isn't supported.

Joel Brobecker writes:
joel> Then let's let the fortran developpers fix it :-).

I agree with Andrew here.  Let's not lie, even if we have to say
"irix_long_double : printf ("not supported\n")" with a big comment
about what we do know.

As far as "default_long_double : printf ("not supported\n")",
I actually like that too!

My two cents,

Michael C