Remove macOS port

We now have a proper native PC port (Moonlight Qt) and if we
wanted to bring the full iOS app over we can now use Catalyst.

Limelight/AppDelegate.h

@@ -6,19 +6,11 @@
 //  Copyright (c) 2014 Moonlight Stream. All rights reserved.
 //
 
-#if TARGET_OS_IPHONE
 #import <UIKit/UIKit.h>
 
 @interface AppDelegate : UIResponder <UIApplicationDelegate>
 
 @property (strong, nonatomic) UIWindow *window;
-#else
-#import <Cocoa/Cocoa.h>
-@interface AppDelegate : NSObject <NSApplicationDelegate>
-
-@property (readonly, strong) NSPersistentContainer *persistentContainer;
-@property (strong, nonatomic) NSWindow *window;
-#endif
 
 @property (readonly, strong, nonatomic) NSManagedObjectContext *managedObjectContext;
 @property (readonly, strong, nonatomic) NSManagedObjectModel *managedObjectModel;