[clang] [clang-sycl-linker] Generate SymbolTable for each image (PR #161287)

[Joseph Huber via cfe-commits]

https://github.com/jhuber6 approved this pull request.

Nothing too offensive, but I feel like part of this should be refactored in the future. You should use LLVM-IR metadata to identify globals of interest and try to avoid needing to create a new string.

https://github.com/llvm/llvm-project/pull/161287