bundle the display-related hints, that tell bot() and others

that an update is required, into a struct. Remove it from
context since there is no reason to save those.

src/teleport.c

@@ -1083,7 +1083,7 @@ dotele(
         } else {
             /* bypassing spelleffects(); apply energy cost directly */
             u.uen -= energy;
-            gc.context.botl = 1;
+            display.botl = 1;
         }
     }