WireGuardKit: Set publicHeadersPath = "." to flatten public headers structure

Signed-off-by: Andrej Mihajlov <and@mullvad.net>

Package.swift

@@ -20,11 +20,13 @@ let package = Package(
         ),
         .target(
             name: "WireGuardKitC",
-            dependencies: []
+            dependencies: [],
+            publicHeadersPath: "."
         ),
         .target(
             name: "WireGuardKitGo",
             dependencies: [],
+            publicHeadersPath: ".",
             linkerSettings: [.linkedLibrary("wg-go")]
         )
     ]

Sources/WireGuardKitC/WireGuardKitC.h

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
 // Copyright © 2018-2019 WireGuard LLC. All Rights Reserved.
 
-#include "../key.h"
-#include "../x25519.h"
+#include "key.h"
+#include "x25519.h"

Sources/WireGuardKitC/module.modulemap

@@ -1,4 +1,4 @@
 module WireGuardKitC {
-    umbrella header "include/WireGuardKitCTarget.h"
+    umbrella header "WireGuardKitC.h"
     export *
 }