Prevent levelporting throughout the Wizard's tower until the Wizard of Yendor has been defeated.

The revamped Wizard's tower was never meant to be skipped through to get
to the Wizard. Levelporting through the Wizard's tower becomes available
only after he has been initially defeated.

Author: k21971

doc/evilhack-changelog.md

@@ -3393,4 +3393,6 @@ The following changes to date are:
 - Underline peaceful monsters via config (tty and curses)
 - New trap: ice
 - Fix: cmap ordering in tilemap.c (addition of ice trap)
+- Prevent levelporting throughout the Wizard's tower until the Wizard of
+  Yendor has been defeated
 

src/potion.c

@@ -1137,7 +1137,7 @@ register struct obj *otmp;
             }
 
             /* revamped wizard's tower is also prohibited */
-            if (Is_wiz2_level(&u.uz) || Is_wiz3_level(&u.uz)) {
+            if (On_W_tower_level(&u.uz)) {
                 You("have an uneasy feeling.");
                 goto no_rise;
             }

src/teleport.c

@@ -863,6 +863,13 @@ level_tele()
             return;
         }
     }
+    /* Prevent levelporting in the Wizard's tower until the
+       Wizard has been defeated for the first time */
+    if (!u.uevent.udemigod && On_W_tower_level(&u.uz)
+        && (!wizard || yn("The Wizard of Yendor has not been defeated.  Override?") != 'y')) {
+        pline("Powerful magic prevents you from teleporting.");
+        return;
+    }
     if ((Teleport_control && !Stunned) || wizard) {
         char qbuf[BUFSZ];
         int trycnt = 0;