I see that this patch makes sense. I'm not sure this really needs a cuda/hip review because I'm not sure that this interface is really ever going to be called by cuda/hip backend.
I'll put my reasoning below for future reference:

For cuda and hip (and I guess some other backends), the interface of urPlatformCreateWithNativeHandle doesn't really matter because I think there should only ever be one platform in these backends consisting of all available devices. And to get this list and construct the platform we don't need any inputs I think.
I may be not taking some requirement into account so I think I should ask @npmiller and @AerialMantis to give their opinions on this since they may have a different point of view.

This is my perspective:

• There's no underlying native platform object in these backends
• It is up to us to define how a platform is defined and can be constructed in these backends. Currently hip and cuda backends can have only one platform when it is constructed by the sycl runtime itself.

Therefore, IMO it should only be ever possible to construct a single platform in these backends, which includes all the devices that are available to the runtime.

There was a proposal that we should define interop native platform in these backends as a vector of devices, which could imply that users could create multiple platforms from a cuda or hip backend, even if the runtime can only ever create one. Having multiple platforms in cuda/hip backends doesn't make any sense to me. We had to do it temporarily in cuda for awkward sycl::context spec issue but this has now been fixed. The fact that we previously had to have multiple platforms in the cuda backend might have been a motivation for this list of devices definition of the native platform, but I think that is out of date now.

But @AerialMantis will know more about this

I don't imagine that other runtimes would behave differently, but I don't know this for sure.

If others agree then this might be a nice time to add some warning or comment in the cuda/hip adapter source stating this interface won't be called in cuda/hip for the above reasons. Just so in the future some poor soul doesn't get roped into trying to work out how to implement it for cuda/hip.

Changes look fine to me, I'll approve this. I made some related points about the relevance of the usage of this function in cuda/hip. IMO we should add a comment in the cuda/hip implementations saying something to the effect that these interop functions don't make sense for cuda/hip backends.
But I see that this is not the main issue of the changes made in this patch.

added a comment explaining the unsupported error codes

LLVM PR intel/llvm#14012

@oneapi-src/level-zero-maintainers please review, this is important for the sycl UR port