Apply visionOS condition to Platform.Darwin.swift

Author: freak4pc

Platform/Platform.Darwin.swift

@@ -6,8 +6,7 @@
 //  Copyright © 2015 Krunoslav Zaher. All rights reserved.
 //
 
-#if os(macOS) || os(iOS) || os(tvOS) || os(watchOS)
-
+#if os(macOS) || os(iOS) || os(tvOS) || os(watchOS) || os(visionOS)
     import Darwin
     import Foundation