[clang-tools-extra] [clang-doc] create a separate cmake file for clang-doc's lit tests (PR #165935)

[Paul Kirth via cfe-commits]

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@@ -0,0 +1,7 @@
+# Specialize the clang-doc target to avoid building other projects
+add_lit_testsuite(check-clang-extra-clang-doc "Running clang-doc tests"
+  ${CMAKE_CURRENT_BINARY_DIR}
+  EXCLUDE_FROM_CHECK_ALL
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ilovepi wrote:

Doesn't that exclude the tests from running under `ninja check-all`? I don't think we want that.

https://github.com/llvm/llvm-project/pull/165935