more TTY_PERM_INVENT, part 3 of 2

Some changes I made while chasing the slots 'A' and 'B' bug.  These
weren't necessary to fix that and I don't think they produce any
change in behavior, aside from making the "Bad window id N" panic
be more specific if it occurs.

src/invent.c

@@ -2500,12 +2500,7 @@ update_inventory(void)
      */
     save_suppress_price = iflags.suppress_price;
     iflags.suppress_price = 0;
-#if defined(TTY_PERM_INVENT)
-    if (WINDOWPORT(tty))
-        sync_perminvent();
-    else
-#endif
-        (*windowprocs.win_update_inventory)(0);
+    (*windowprocs.win_update_inventory)(0);
     iflags.suppress_price = save_suppress_price;
 }