This adds an ICD entrypoint for vkGetPhysicalDeviceWin32PresentationSupportKHR
to the Win32 platform.

This change will allow tools that make use of this function to work with the
swiftshader ICD. One such tool is my Vulkan Hardware Capability viewer, that
would crash on ICDs not implementing this.

Bug: b/143207519
Change-Id: I23552cf072595b97f3032416a51c0db13d3f87a9
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/37509
Presubmit-Ready: Alexis Hétu <sugoi@google.com>
Kokoro-Presubmit: kokoro <noreply+kokoro@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>
Tested-by: Alexis Hétu <sugoi@google.com>