port: Fix usage output for actions with portlists

src/port/port.tcl

@@ -1717,7 +1717,7 @@ proc action_get_usage { action } {
         set needed [action_needs_portlist $action]
         if {[ACTION_ARGS_STRINGS] == $needed} {
             set args " <arguments>"
-        } elseif {[ACTION_ARGS_STRINGS] == $needed} {
+        } elseif {[ACTION_ARGS_PORTS] == $needed} {
             set args " <portlist>"
         }