[vte] parser: modes: Small doc addition

[Christian Persch <chpe src gnome org>]

commit ed2ca9ff126aed6ddb9274611415f5a8239fa25f
Author: Christian Persch <chpe src gnome org>
Date:   Sat Apr 3 16:07:50 2021 +0200

    parser: modes: Small doc addition

 src/modes.py | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/src/modes.py b/src/modes.py
index 9c308875..efb69737 100755
--- a/src/modes.py
+++ b/src/modes.py
@@ -543,6 +543,7 @@ modes = [
     #mode_WHAT('DECGPCM', 44, default=False),
 
     # DECGCPS - Graphics Print Colour Syntax
+    # If set, uses RGB colour format; if reset, uses HLS colour format.
     #
     # Default: reset
     #