[cogl] Fix a warning in the EGL winsys

[Neil Roberts <nroberts src gnome org>]

commit d0290eb19fc9bf56fb24f8eab573e19966ea7e1a
Author: Neil Roberts <neil linux intel com>
Date:   Thu May 30 13:57:56 2013 +0100

    Fix a warning in the EGL winsys
    
    _cogl_egl_query_wayland_buffer was using _COGL_RETURN_IF_FAIL but the
    function needs to return a CoglBool so it was giving a warning.

 cogl/winsys/cogl-winsys-egl.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/cogl/winsys/cogl-winsys-egl.c b/cogl/winsys/cogl-winsys-egl.c
index 73b9a88..4ccebcd 100644
--- a/cogl/winsys/cogl-winsys-egl.c
+++ b/cogl/winsys/cogl-winsys-egl.c
@@ -1051,7 +1051,7 @@ _cogl_egl_query_wayland_buffer (CoglContext *ctx,
 {
   CoglRendererEGL *egl_renderer = ctx->display->renderer->winsys;
 
-  _COGL_RETURN_IF_FAIL (egl_renderer->pf_eglQueryWaylandBuffer);
+  _COGL_RETURN_VAL_IF_FAIL (egl_renderer->pf_eglQueryWaylandBuffer, FALSE);
 
   return egl_renderer->pf_eglQueryWaylandBuffer (egl_renderer->edpy,
                                                  buffer,