configure: when compiling with CLANG, set -std=gnu89

[Austin English]

On Wed, Apr 14, 2010 at 10:19 AM, Alexandre Julliard
<julliard at winehq.org> wrote:
> Austin English <austinenglish at gmail.com> writes:
>
>> Clang defaults to compiling in C99 mode, which breaks the compile.
>
> Of course the compile should be fixed instead.

Not entirely trivial, since the compile is broken for gcc in c99 mode as well:
http://bugs.winehq.org/show_bug.cgi?id=20474

-- 
-Austin