Includes update to to_string functionality that reports enum value in
case of "invalid".

https://github.com/KhronosGroup/Vulkan-Headers
revision 670ffea9d61b9f4b8f68c919dab7caf33dfd9718
tag v1.2.160

Bug: b/170962162
Test: build
Change-Id: I5ac872bdebd7f8898bda78a7b7f025da9e7cd21d
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/50348Reviewed-by: Alexis Hétu <sugoi@google.com>
Reviewed-by: Nicolas Capens <nicolascapens@google.com>
Tested-by: Sean Risser <srisser@google.com>