layers: Add VK_NV_external_memory_win32 ext to OT
layers: Add VK_NV_external_memory_win32 ext to OT

Added GetMemoryWin32HandleNV API for this extension to object_tracker.

Change-Id: I94cc6a3928f90c6ff964f7a2e5cba9aa2548d653

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