missed this const fix

src/ship/ship.rs

@@ -390,9 +390,11 @@ pub struct Block {
 
 impl Default for Block {
     fn default() -> Block {
+        const SNONE: Option<room::RoomState> = None;
+        const NONE: Rooms = [SNONE; MAX_ROOMS];
         Block {
             client_location: Box::new(ClientLocation::default()),
-            rooms: Box::new([None; MAX_ROOMS]),
+            rooms: Box::new(NONE),
         }
     }
 }