[SYCL][NFC] Cache the sycl::device instance in queue_impl

[slawekptak]

[slawekptak]

@aelovikov-intel @lbushi25 Please see, if this kind of change could solve the shared_ptr unnecessary copies (for the device in this case). Thanks.

[aelovikov-intel]

I think a better change would be to make platform/device use raw pointers instead of std::shared_ptr for their impls. That should come together with detail::ObjBase like in @KseniyaTikhomirova 's https://github.com/llvm/llvm-project/pull/166927.

I'm starting to work on that refactoring.

[slawekptak]

I think a better change would be to make platform/device use raw pointers instead of std::shared_ptr for their impls. That should come together with detail::ObjBase like in @KseniyaTikhomirova 's llvm/llvm-project#166927.

I'm starting to work on that refactoring.

Ok, let's do this then. Please feel free to include me in the review of that refactoring PR.