fix copypaste error in log message

ttcn/Security/LibItsSecurity_Functions.ttcn3

@@ -1218,7 +1218,7 @@ module LibItsSecurity_Functions {
                             log("f_loadCertificates: Failed to load AA certificate for ", cc_taCert_A);
                         }
                     }else{
-                        log("f_loadCertificates: Failed to load AA certificate for ", cc_taCert_A);
+                        log("f_loadCertificates: Failed to load AT certificate for ", cc_taCert_A);
                     }
                 }else{
                     log("f_loadCertificates: Failed to load certificates from ", PX_CERTIFICATE_POOL_PATH);