weston-log: rename the confusing function name weston_compositor_log_scope_destroy()

There's a function named weston_compositor_log_scope_destroy()
but it doesn't take a struct weston_compositor argument.

Rename it to weston_log_scope_destroy(), as the argument is a
struct weston_log_scope.

Signed-off-by: Leandro Ribeiro <leandrohr@riseup.net>
diff --git a/libweston/compositor.c b/libweston/compositor.c
index 0a70c27..0166b73 100644
--- a/libweston/compositor.c
+++ b/libweston/compositor.c
@@ -7699,10 +7699,10 @@
 	if (compositor->heads_changed_source)
 		wl_event_source_remove(compositor->heads_changed_source);
 
-	weston_compositor_log_scope_destroy(compositor->debug_scene);
+	weston_log_scope_destroy(compositor->debug_scene);
 	compositor->debug_scene = NULL;
 
-	weston_compositor_log_scope_destroy(compositor->timeline);
+	weston_log_scope_destroy(compositor->timeline);
 	compositor->timeline = NULL;
 }