[gnome-software/wip/mak/libas] build: Use C11 standard

[Philip Withnall <pwithnall src gnome org>]

commit f61d690676f4fa73cb7dcdf996f925bf2d054a2f
Author: Matthias Klumpp <matthias tenstral net>
Date:   Wed Feb 10 19:07:20 2021 +0100

    build: Use C11 standard
    
    It’s needed for building appstream as a subproject, and there’s no
    reason gnome-software shouldn’t move to C11 anyway. So let’s move.
    
    (Commit message updated by Philip Withnall.)

 meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/meson.build b/meson.build
index 7de3149d6..612764070 100644
--- a/meson.build
+++ b/meson.build
@@ -1,7 +1,7 @@
 project('gnome-software', 'c',
   version : '40.beta',
   license : 'GPL-2.0+',
-  default_options : ['warning_level=1', 'c_std=c99'],
+  default_options : ['warning_level=1', 'c_std=c11'],
   meson_version : '>=0.47.0'
 )