[clang-tools-extra] [clang-doc] Add Markdown AST node type definitions (PR #205609)

[Neil Nair via cfe-commits]

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@@ -5,6 +5,13 @@ set(LLVM_LINK_COMPONENTS
   )
 
 add_clang_library(clangDocSupport STATIC
+  PARTIAL_SOURCES_INTENDED
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Neil-N4 wrote:

Needed since Markdown.cpp and File.cpp/Utils.cpp share a directory but build into two targets. happy to move Markdown to its own subdirectory if you'd rather

https://github.com/llvm/llvm-project/pull/205609