Display an error on net conf import failures.

When something goes wrong, such as a typo in a parameter
name, we'll now display the failure instead of just returning
with -1 and no message.

source3/utils/net_conf.c

@@ -229,6 +229,9 @@ static WERROR import_process_service(struct net_context *c,
 						     service->param_names[idx],
 						     service->param_values[idx]);
 			if (!W_ERROR_IS_OK(werr)) {
+				d_printf("Error in section [%s], parameter \"%s\": %s\n",
+					 service->name, service->param_names[idx],
+					 win_errstr(werr));
 				goto done;
 			}
 		}