[gnome-remote-desktop] rdp-graphics-pipeline: Extend comment with documentation reference

[Jonas Ådahl <jadahl src gnome org>]

commit c3b1c75e76566b83c623bd2387dce273ee7ec1ac
Author: Pascal Nowack <Pascal Nowack gmx de>
Date:   Fri Aug 5 11:31:42 2022 +0200

    rdp-graphics-pipeline: Extend comment with documentation reference
    
    In case someone reads the documentation, the connection between the
    documentation and the implementation would be clearer.

 src/grd-rdp-graphics-pipeline.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/grd-rdp-graphics-pipeline.c b/src/grd-rdp-graphics-pipeline.c
index e7dafb80..3b525e60 100644
--- a/src/grd-rdp-graphics-pipeline.c
+++ b/src/grd-rdp-graphics-pipeline.c
@@ -90,7 +90,7 @@ struct _GrdRdpGraphicsPipeline
   GHashTable *surface_table;
   GHashTable *codec_context_table;
 
-  /* Unacknowledged Frames ADM element */
+  /* Unacknowledged Frames ADM element ([MS-RDPEGFX] 3.2.1.2) */
   GHashTable *frame_serial_table;
 
   GHashTable *serial_surface_table;