[clang] [Clang][SYCL] Introduce clang-sycl-link-wrapper to link SYCL offloading device code (Part 1 of many) (PR #112245)

[Arvind Sudarsanam via cfe-commits]

asudarsa wrote:

This PR is the first in the list of multiple PRs that will be submitted to add SYCL offloading support using the new offloading model. Upcoming PRs include:
1. SYCL finalization steps that will run after llvm-link will be added to the linking clow inside clang-sycl-link-wrapper. One of the finalization steps is device code splitting.
2. Changes to clang-linker-wrapper to invoke the clang-sycl-link-wrapper (via the clang driver call) for SYCL offloading case.
3. AOT compilation support for Intel, AMD and NVidia GPUs

Thanks
Sincerely

https://github.com/llvm/llvm-project/pull/112245