[mutter] wayland/surface: Simplify is_child & is_sibling

[Marge Bot <marge-bot src gnome org>]

commit ddb7f842911a3a9d7296cecb2bba7638c264c9a9
Author: Michel Dänzer <mdaenzer redhat com>
Date:   Fri Jun 17 16:29:34 2022 +0200

    wayland/surface: Simplify is_child & is_sibling
    
    Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2525>

 src/wayland/meta-wayland-subsurface.c | 10 ++--------
 1 file changed, 2 insertions(+), 8 deletions(-)
---
diff --git a/src/wayland/meta-wayland-subsurface.c b/src/wayland/meta-wayland-subsurface.c
index ef6f6657bf..4055e68820 100644
--- a/src/wayland/meta-wayland-subsurface.c
+++ b/src/wayland/meta-wayland-subsurface.c
@@ -95,20 +95,14 @@ static gboolean
 is_child (MetaWaylandSurface *surface,
           MetaWaylandSurface *sibling)
 {
-  if (surface->sub.parent == sibling)
-    return TRUE;
-  else
-    return FALSE;
+   return surface->sub.parent == sibling;
 }
 
 static gboolean
 is_sibling (MetaWaylandSurface *surface,
             MetaWaylandSurface *sibling)
 {
-  if (surface->sub.parent == sibling->sub.parent)
-    return TRUE;
-  else
-    return FALSE;
+  return surface->sub.parent == sibling->sub.parent;
 }
 
 static gboolean