systemctl: cat: fix error handling

- correctly check for local vs. remote transport
- return after receiving error from expand_names()

(cherry picked from commit 3e7eed8497)

Conflicts:
	src/systemctl/systemctl.c

src/systemctl/systemctl.c

@@ -4544,14 +4544,16 @@ static int cat(sd_bus *bus, char **args) {
         assert(bus);
         assert(args);
 
-        if (arg_host) {
-                log_error("Option --host cannot be used with 'cat'");
+        if (arg_transport != BUS_TRANSPORT_LOCAL) {
+                log_error("Cannot remotely cat units");
                 return -EINVAL;
         }
 
         r = expand_names(bus, args + 1, NULL, &names);
-        if (r < 0)
+        if (r < 0) {
                 log_error("Failed to expand names: %s", strerror(-r));
+                return r;
+        }
 
         pager_open_if_enabled();