[clang-tools-extra] [clang-tidy] Fix readability-simplify-boolean-expr for init statements (PR #172220)

[via cfe-commits]

github-actions[bot] wrote:

<!--PREMERGE ADVISOR COMMENT: Linux-->
# :penguin: Linux x64 Test Results

* 3053 tests passed
* 7 tests skipped
* 1 test failed

## Failed Tests
(click on a test name to see its output)

### Clang Tools
<details>
<summary>Clang Tools.clang-tidy/checkers/readability/simplify-boolean-expr-cxx17.cpp</summary>

```
Exit Code: 1

Command Output (stdout):
--
# RUN: at line 1
clang-tidy /home/gha/actions-runner/_work/llvm-project/llvm-project/clang-tools-extra/test/clang-tidy/checkers/readability/simplify-boolean-expr-cxx17.cpp -checks='-*,readability-simplify-boolean-expr' -- -std=c++17 | count 0
# executed command: clang-tidy /home/gha/actions-runner/_work/llvm-project/llvm-project/clang-tools-extra/test/clang-tidy/checkers/readability/simplify-boolean-expr-cxx17.cpp '-checks=-*,readability-simplify-boolean-expr' -- -std=c++17
# .---command stderr------------
# | 2 warnings generated.
# `-----------------------------
# executed command: count 0
# .---command stderr------------
# | Expected 0 lines, got 20.
# `-----------------------------
# error: command failed with exit status: 1

--

```
</details>

If these failures are unrelated to your changes (for example tests are broken or flaky at HEAD), please open an issue at https://github.com/llvm/llvm-project/issues and add the `infrastructure` label.

https://github.com/llvm/llvm-project/pull/172220