updated window_procs

Add a non-string identifier to window_procs for use in runtime
identification of the current window port being used.

Use a macro WPID to add the identification at the top of the
various existing window_procs declarations. It expands to the
existing text string, as well as the newly added field wp_id
with a wp_ identifier.

For example, WPID(tty) expands to: "tty", wp_tty

The generated wp_tty must be present in the wp_ids enum at
the top of include/winprocs.h.

The WINDOWPORT(x) macro has been updated to expand to a simple
value comparison (port.wp_id == wp_x), instead of a
string comparison.

win/Qt/qt_bind.cpp

@@ -1033,7 +1033,7 @@ static void Qt_positionbar(char *) {}
 } // namespace nethack_qt_
 
 struct window_procs Qt_procs = {
-    "Qt",
+    WPID(Qt),
     (WC_COLOR | WC_HILITE_PET
      | WC_ASCII_MAP | WC_TILED_MAP
      | WC_FONT_MAP | WC_TILE_FILE | WC_TILE_WIDTH | WC_TILE_HEIGHT