[llvm] [bazel] Update tblgen rules to support path-mapping (PR #158354)

[Keith Smiley via llvm-commits]

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@@ -234,15 +222,16 @@ def _gentbl_test_impl(ctx):
     # workspace is not the main workspace. Therefore it is not included in the
     # _resolve_includes call that prepends this prefix.
     trans_includes = _get_transitive_includes(
-        _resolve_includes(ctx, ctx.attr.includes + ["/"]) +
-        _prefix_roots(ctx, [td_file.dirname]),
+        _resolve_includes(ctx, ctx.attr.includes + ["/"]) + [td_file.dirname],
         ctx.attr.deps,
     )
 
     test_args = [ctx.executable.tblgen.short_path]
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keith wrote:

yea shouldn't be a big deal either since that would only affect things if this test itself was under a transition

https://github.com/llvm/llvm-project/pull/158354