2.18 ar/ranlib glitch for mips elf64

[Paul Koning]

Gents,

In trying to build a toolchain that can handle MIPS N64, I ran into an
issue for that case.  I built a pile of object files (those are
elf64-tradlittlemips BFD format).  Built an archive with "ar cq" and
that worked.  But then attempts to look at that archive with ar or
ranlib fail with "File format is ambiguous" and "matching formats:
elf64-tradlittlemips ecoff-littlemips ecoff-bigmips".

I noticed the same issue applies to the libgcc.a that the GCC build
process creates.  Readelf tells me that every member in the archive is
elf64, so I have no idea where those ecoff things come from.  I see no
way to tell ar what the actual format is.

Should I use a newer binutils?  Should I yank ecoff support out?  (That
certainly wouldn't bother me...)

	paul