[committed] Add a MIPS -msym32 option

[Richard Sandiford]

Richard Sandiford <rsandifo@redhat.com> writes:
> Although this is a new feature, it's about as non-invasive as a new
> feature can get, and I'd like to apply it to 4.0 branch if possible.
> The main reason is that it's likely that binutils 2.16 will be coming
> out at about the same time as gcc 4.0.0, and it would be nice to have
> both of them support the option.  On the other hand, I realise that
> adding a patch like this 4.0 isn't really in keeping with the
> development plan, so I won't ask formally unless a couple of
> other folks "sponsor" the suggestion.

Well, Daniel J. gave his vote and Eric C. seemed OK with it.  It sounds
like target maintainers are allowed to approve this kind of thing, so I
went ahead and committed it to 4.0.  Will update the 4.0 changes.html
in a sec.

Richard