layers: Fix core_validation Win32 build
layers: Fix core_validation Win32 build

Change-Id: Ib15d5c6fad234c0d657b59613293f38d28969697

KhronosGroup/Vulkan-Tools,KhronosGroup/Vulkan-Tools,KhronosGroup/Vulkan-Tools,KhronosGroup/Vulkan-Tools