[clang] [clang-sycl-linker] AOT-compile split modules concurrently (PR #224548)

[Wenju He via cfe-commits]

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@@ -924,6 +925,54 @@ static bool canSkipModuleSplit(IRSplitMode Mode, const Module &M,
   });
 }
 
+/// AOT-compiles every already-produced image in \p SplitModules concurrently
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wenju-he wrote:

done, changed to "JIT image"

https://github.com/llvm/llvm-project/pull/224548