Removed all code in Y_FollowIntermission that's already handled in G_AfterIntermission

Only real difference here is that CEcho messages will always be cleared when going to credits/evaluation, but that's hardly a loss tbh.

src/g_game.c

@@ -2999,10 +2999,10 @@ static void G_DoContinued(void)
 
 //
 // G_EndGame (formerly Y_EndGame)
-// Franky this function fits better in g_game.c than it does in y_inter.c
+// Frankly this function fits better in g_game.c than it does in y_inter.c
 //
 // ...Gee, (why) end the game?
-// Because Y_FollowIntermission and F_EndCutscene would
+// Because G_AfterIntermission and F_EndCutscene would
 // both do this exact same thing *in different ways* otherwise,
 // which made it so that you could only unlock Ultimate mode
 // if you had a cutscene after the final level and crap like that.

src/y_inter.c

@@ -1805,21 +1805,10 @@ static void Y_FollowIntermission(void)
 		return;
 	}
 
-	if (nextmap < 1100-1)
-	{
-		// normal level
-		G_AfterIntermission();
-		return;
-	}
-
-	// Start a custom cutscene if there is one.
-	if (mapheaderinfo[gamemap-1]->cutscenenum && !modeattacking)
-	{
-		F_StartCustomCutscene(mapheaderinfo[gamemap-1]->cutscenenum-1, false, false);
-		return;
-	}
-
-	G_EndGame();
+	// This handles whether to play a post-level cutscene, end the game,
+	// or simply go to the next level.
+	// No need to duplicate the code here!
+	G_AfterIntermission();
 }
 
 #define UNLOAD(x) Z_ChangeTag(x, PU_CACHE); x = NULL