[librsvg] Add deprecation attribute to rsvg_cleanup

[Federico Mena Quintero <federico src gnome org>]

commit 661643cf7efd2a757759e74870d74e9e2af6f917
Author: Federico Mena Quintero <federico gnome org>
Date:   Thu Dec 27 19:02:57 2018 -0600

    Add deprecation attribute to rsvg_cleanup

 librsvg/rsvg.h | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/librsvg/rsvg.h b/librsvg/rsvg.h
index db9f8f7f..1a803a9a 100644
--- a/librsvg/rsvg.h
+++ b/librsvg/rsvg.h
@@ -151,6 +151,7 @@ struct _RsvgRectangle {
 };
 
 
+RSVG_DEPRECATED
 void rsvg_cleanup (void);
 
 RSVG_DEPRECATED