[clang-tools-extra] Fix Default Asset File locator for clang docs (PR #97505)

[Damyan Pepper via cfe-commits]

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@@ -44,7 +42,10 @@ foreach(f ${assets})
   install(FILES ${asset_dir}/${f}
     DESTINATION "${CMAKE_INSTALL_DATADIR}/clang-doc"
     COMPONENT clang-doc)
-  copy_files_to_dst(${asset_dir} ${resource_dir} ${f})
+   foreach(config ${CMAKE_CONFIGURATION_TYPES})
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damyanp wrote:

Do ninja / other single-config build systems still work?  I think that `CMAKE_CONFIGURATION_TYPES` is blank for single configuration systems.

https://github.com/llvm/llvm-project/pull/97505