Teleport traps don't teleport you on no-teleport levels

In previous versions of NetHack, this wasn't a problem because
teleport traps didn't *generate* on such levels, but more recent
changes have made this situation possible (e.g. a demon lord
migrates to a Gehennom filler level that already had a teleport
trap on it).

This change causes a "wrenching sensation", like stepping onto a
teleport trap with magic resistance does.

src/teleport.c

@@ -1494,7 +1494,7 @@ tele_trap(struct trap *trap)
         return;
 
     in_tele_trap = TRUE;
-    if (In_endgame(&u.uz) || Antimagic) {
+    if (In_endgame(&u.uz) || Antimagic || noteleport_level(&gy.youmonst)) {
         if (Antimagic)
             shieldeff(u.ux, u.uy);
         You_feel("a wrenching sensation.");