[glib-networking/c99] meson: use c std c99

[Ignacio Casal Quinteiro <icq src gnome org>]

commit 2c75942d6a054a0f39c8847ce5e7ebaefa575a6f
Author: Ignacio Casal Quinteiro <qignacio amazon com>
Date:   Thu Sep 26 16:12:05 2019 +0200

    meson: use c std c99
    
    c11 is not supported on centos 6 nor on Visual Studio which
    does not even fully supports c99

 meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/meson.build b/meson.build
index 7d3e3c7..1fc7612 100644
--- a/meson.build
+++ b/meson.build
@@ -3,7 +3,7 @@ project(
   version: '2.62.0',
   license: 'LGPL2.1+',
   meson_version: '>= 0.50.0',
-  default_options: ['c_std=c11']
+  default_options: ['c_std=c99']
 )
 
 prefix = get_option('prefix')