remove unneeded forward declaration

this is already taken care of by vk_platform.h

Test: compiled & booted
Bug: 35164655

Change-Id: Ie7574cfe985fed86922c923ca3b2225e017c2d5a
diff --git a/vulkan/include/vulkan/vulkan.h b/vulkan/include/vulkan/vulkan.h
index 0980f24..33ed5be 100644
--- a/vulkan/include/vulkan/vulkan.h
+++ b/vulkan/include/vulkan/vulkan.h
@@ -3702,7 +3702,6 @@
 
 #ifdef VK_USE_PLATFORM_ANDROID_KHR
 #define VK_KHR_android_surface 1
-struct ANativeWindow;
 
 #define VK_KHR_ANDROID_SURFACE_SPEC_VERSION 6
 #define VK_KHR_ANDROID_SURFACE_EXTENSION_NAME "VK_KHR_android_surface"