[clang-tools-extra] [clang-tools-extra][docs] Add "Potentially Breaking Changes" section to ReleaseNotes (PR #158434)

[Baranov Victor via cfe-commits]

https://github.com/vbvictor created https://github.com/llvm/llvm-project/pull/158434

This implements
https://github.com/llvm/llvm-project/blob/30e9cbacab5b474de89992851f126fff300c1ab7/llvm/docs/DeveloperPolicy.rst?plain=1#L282-L286
>From LLVM developer policy.

>From 48d649852c83807b80dfbd966bef38902bafeeee Mon Sep 17 00:00:00 2001
From: Victor Baranov <bar.victor.2002 at gmail.com>
Date: Sat, 13 Sep 2025 22:59:29 +0300
Subject: [PATCH] [clang-tools-extra][docs] Add "Potentially Breaking Changes"
 to ReleaseNotes.rst

---
 clang-tools-extra/docs/ReleaseNotes.rst         | 15 +++++++++++++++
 clang-tools-extra/docs/ReleaseNotesTemplate.txt |  3 +++
 2 files changed, 18 insertions(+)

diff --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst
index 34091906cbff2..7cdff86beeec6 100644
--- a/clang-tools-extra/docs/ReleaseNotes.rst
+++ b/clang-tools-extra/docs/ReleaseNotes.rst
@@ -46,6 +46,21 @@ infrastructure are described first, followed by tool-specific sections.
 Major New Features
 ------------------
 
+Potentially Breaking Changes
+----------------------------
+
+- Removed :program:`clang-tidy`'s global options `IgnoreMacros` and
+  `StrictMode`, which were documented as deprecated since
+  :program:`clang-tidy-20`. Users should use the check-specific options of the
+  same name instead.
+
+- Renamed :program:`clang-tidy`'s option name of check
+  :doc:`bugprone-easily-swappable-parameters
+  <clang-tidy/checks/bugprone/easily-swappable-parameters>` from
+  ``NamePrefixSuffixSilenceDissimilarityTreshold`` to
+  ``NamePrefixSuffixSilenceDissimilarityThreshold``,
+  correcting a spelling mistake.
+
 Improvements to clangd
 ----------------------
 
diff --git a/clang-tools-extra/docs/ReleaseNotesTemplate.txt b/clang-tools-extra/docs/ReleaseNotesTemplate.txt
index b17799b3b557d..69c3bcf67b8db 100644
--- a/clang-tools-extra/docs/ReleaseNotesTemplate.txt
+++ b/clang-tools-extra/docs/ReleaseNotesTemplate.txt
@@ -46,6 +46,9 @@ infrastructure are described first, followed by tool-specific sections.
 Major New Features
 ------------------
 
+Potentially Breaking Changes
+----------------------------
+
 Improvements to clangd
 ----------------------