Add rules for ObjC files

[Adam Fedor]

  Andrew Cagney wrote:

>> Klee Dienes wrote:
>> ObjC is supposed to be a strict superset of C, so at least in theory,
>> extensions don't need to be conditionalized at all, or they can be
>> disallowed after parsing, if you wanted to have a "strict C mode"
>> (although I note that the little array@45 extension is always available,
>> even though it's not valid C).
>
>
>
> (time passes)
>
> (array@45 is documented as a GDB CLI extension).
>
> Keeping the objective C .y separate from the C .y, I think, is a 
> better long term strategy.  While it will mean that someone needs to 
> keep the two files in sync, it also means that the objective C, C and 
> C++ parsers are guarenteed to not stomp on each others toes.
>

Well since the parsers probably aren't going to be combined yet :-) I'll 
un-withdraw this patch. Can someone approve it?

-- 
Adam Fedor, Digital Optics Corp.      | I'm glad I hate spinach, because
http://www.doc.com                    | if I didn't, I'd eat it, and you
                                       | know how I hate the stuff.