[SYCL][Bindless] Add mipmap interop + slight redesign + bug fix (#12736)
Mipmap interop:
- Remove "interop" image type as it is redundant for image creation
- Add a vulkan mipmap interop test
Slight redesign:
- Simplify external resources
Modify the bindless spec to reflect these changes
Fix Vulkan interop tests to prevent memory leak issue by freeing mapped
memory
Corresponding UR PR:
https://github.com/oneapi-src/unified-runtime/pull/1351
Depends on https://github.com/intel/llvm/pull/12784 merging first
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Co-authored-by: DBDuncan <43582941+DBDuncan@users.noreply.github.com>