ad-auth: fix a typo in handler

ad-auth/handlers/main.yml

@@ -8,7 +8,7 @@
   command: sss_cache -E
   register: result
   changed_when: "result.rc == 0"
-  failed_when: "result.rc != 0 and current_realms.rc != 2"
+  failed_when: "result.rc != 0 and result.rc != 2"
 
 - name: restart sssd
   service: name=sssd state=restarted