[llvm] [Bazel] Add a comment why an export file is needed. (PR #115556)

[weiwei chen via llvm-commits]

https://github.com/weiweichen created https://github.com/llvm/llvm-project/pull/115556

- [x] Add follow-up comment on why the export file is needed in BUILD.bazel

>From 41e93082fa063daf040976b4f446238cd041f41f Mon Sep 17 00:00:00 2001
From: Weiwei Chen <weiwei.chen at modular.com>
Date: Fri, 8 Nov 2024 17:17:06 -0500
Subject: [PATCH] Add a comment why an export file is needed.

---
 utils/bazel/llvm-project-overlay/llvm/BUILD.bazel | 1 +
 1 file changed, 1 insertion(+)

diff --git a/utils/bazel/llvm-project-overlay/llvm/BUILD.bazel b/utils/bazel/llvm-project-overlay/llvm/BUILD.bazel
index 7206995334467c..0628947540ca73 100644
--- a/utils/bazel/llvm-project-overlay/llvm/BUILD.bazel
+++ b/utils/bazel/llvm-project-overlay/llvm/BUILD.bazel
@@ -32,6 +32,7 @@ exports_files([
     "include/llvm/IR/Intrinsics.td",
     "include/llvm/Option/OptParser.td",
     "utils/lit/lit.py",
+    # This one is needed for building and vendoring out lldb from off tree.
     "utils/lldbDataFormatters.py",
 ])