Fix comparing wipegamestate with FORCEWIPE

Fun fact: the signedness of an enumeration is up to the implementation!

src/d_main.cpp

@@ -596,6 +596,7 @@ static void D_Display(void)
 			}
 		case GS_DEDICATEDSERVER:
 		case GS_NULL:
+		case FORCEWIPE:
 			break;
 	}
 

src/f_finale.h

@@ -26,9 +26,6 @@ extern "C" {
 //
 // FINALE
 //
-// HACK for menu fading while titlemapinaction; skips the level check
-#define FORCEWIPE -2
-
 
 // Called by main loop.
 boolean F_IntroResponder(event_t *ev);

src/g_game.c

@@ -2277,6 +2277,7 @@ void G_Ticker(boolean run)
 
 		case GS_DEDICATEDSERVER:
 		case GS_NULL:
+		case FORCEWIPE:
 			break; // do nothing
 	}
 

src/g_state.h

@@ -22,6 +22,7 @@ extern "C" {
 // the current state of the game
 typedef enum
 {
+	FORCEWIPE = -2,     // HACK for menu fading while titlemapinaction; skips the level check
 	GS_NULL = 0,        // At beginning.
 
 	// Fadable gamestates