[gnome-control-center] printers: Fix double free / leak due to copy-paste error

[Robert Ancell <rancell src gnome org>]

commit ed78a6a12057677788cde811634b18cd9710e86d
Author: Robert Ancell <robert ancell canonical com>
Date:   Fri Jun 15 15:49:10 2018 +1200

    printers: Fix double free / leak due to copy-paste error

 panels/printers/pp-ppd-option-widget.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/panels/printers/pp-ppd-option-widget.c b/panels/printers/pp-ppd-option-widget.c
index f7d0bf45c..383823af9 100644
--- a/panels/printers/pp-ppd-option-widget.c
+++ b/panels/printers/pp-ppd-option-widget.c
@@ -190,8 +190,8 @@ pp_ppd_option_widget_finalize (GObject *object)
 
       if (priv->option_name)
         {
-          g_free (priv->printer_name);
-          priv->printer_name = NULL;
+          g_free (priv->option_name);
+          priv->option_name = NULL;
         }
 
       if (priv->destination)