[krb5-auth-dialog] kerberos: Use g_autofree

[Guido Günther <guidog src gnome org>]

commit 1478ecfe99b6af45854dedb2a3a4e832e85a58a9
Author: Guido Günther <agx sigxcpu org>
Date:   Mon Oct 17 10:13:53 2022 +0200

    kerberos: Use g_autofree

 src/ka-kerberos.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)
---
diff --git a/src/ka-kerberos.c b/src/ka-kerberos.c
index caf1339..da0f55e 100644
--- a/src/ka-kerberos.c
+++ b/src/ka-kerberos.c
@@ -1005,13 +1005,10 @@ ka_grab_credentials (KaApplet *applet)
         if (canceled)
             break;
         if (retval) {
-            gchar *errmsg;
-
-            errmsg = g_strdup_printf("%s%s",
-                                     ka_get_error_message (kcontext, retval),
-                                     is_online ? "" : _(" (No network connection)"));
+            g_autofree char *errmsg = g_strdup_printf("%s%s",
+                                                      ka_get_error_message (kcontext, retval),
+                                                      is_online ? "" : _(" (No network connection)"));
             ka_pwdialog_error (pwdialog, errmsg);
-            g_free (errmsg);
             break;
         } else {
             success = TRUE;