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

[Yury Plyakhin via cfe-commits]

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@@ -523,12 +545,13 @@ Error runSYCLLink(ArrayRef<std::string> Files, const ArgList &Args) {
         return createFileError(File, EC);
     }
     OffloadingImage TheImage{};
-    TheImage.TheImageKind = IMG_Object;
+    TheImage.TheImageKind = IMG_None;
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YuriPlyakhin wrote:

At this point yes, there are problems, if we use `IMG_SPIRV` and `IMG_Object` due to incompatibility between data format used in upstream and Intel's compiler forks. I tried using `IMG_SPIRV`, etc. and it opens can of worms.
I plan to do the clean-up and sync structures between upstream and Intel's forks, but it is definitely a separate PR.
For this PR I used `IMG_None`, because in that case at least SYCL runtime has a heuristic to understand what the Image Kind is, so we can at least verify that overall compilation/linking scheme works.

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