[llvm] [llvm-rc] Accept filenames provided as multiple string literals (PR #68881)

[Martin Storsjö via llvm-commits]

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@@ -0,0 +1,2 @@
+100 ICON "subdir" "/icon-new.ico"
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mstorsjo wrote:

That'd be nicer - but we can't use the preprocessor in these tests. We're building llvm-rc as part of llvm, and llvm tests can't depend on clang. So all the llvm-rc tests run with `-no-preprocessor` to skip that step.

https://github.com/llvm/llvm-project/pull/68881