[mutter] cogl: Remove reference to nonexistent type CoglVertex2f

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit 02db9ee577af479aa26fe73c6a0023b5e79e136d
Author: Daniel van Vugt <daniel van vugt canonical com>
Date:   Wed Dec 18 11:58:27 2019 +0800

    cogl: Remove reference to nonexistent type CoglVertex2f
    
    It is actually CoglVertexP2.
    
    https://gitlab.gnome.org/GNOME/mutter/merge_requests/979

 cogl/cogl/cogl-indices.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/cogl/cogl/cogl-indices.h b/cogl/cogl/cogl-indices.h
index 5a1f3beb5..713b8c66f 100644
--- a/cogl/cogl/cogl-indices.h
+++ b/cogl/cogl/cogl-indices.h
@@ -76,7 +76,7 @@ G_BEGIN_DECLS
  * vertices multiple times.
  *
  * |[
- *   CoglVertex2f quad_vertices[] = {
+ *   CoglVertexP2 quad_vertices[] = {
  *     {x0, y0}, //0 = top left
  *     {x1, y1}, //1 = bottom left
  *     {x2, y2}, //2 = bottom right