[llvm] [libsycl] Add sycl::queue stub (PR #184110)

[Kseniya Tikhomirova via llvm-commits]

KseniyaTikhomirova wrote:

Hi @tahonermann, @dvrogozh, @sergey-semenov, @bader, @againull, @dm-vodopyanov,
I've created a new SYCL RT PR with sycl::queue stub for initial USM alloc & free funcs impl. This is second part (part 1 is merged). 

thanks.

https://github.com/llvm/llvm-project/pull/184110