Enable additional clang-tidy checks

These checks are all fast, worthwhile, and currently pass.

Also update comment in static_analysis_toolchain.gni.

Runtime impact: On my workstation I ran,

    for i in 1 2 3;
    do gn clean out; gn gen out; time ninja -C out static_analysis;
    done

with and without this change.  The mean CPU time (user+sys) increased by
about 25%, from 559 s to 707 s.  I think this is acceptable.

No-Docs-Update-Reason: We do not currently discuss in the documentation which clang-tidy checks are run for upstream pigweed itself.
Change-Id: If28652ecbd3ca6c876e6942d08d24a30717e8294
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/66440
Commit-Queue: Ted Pudlik <tpudlik@google.com>
Reviewed-by: Rob Mohr <mohrr@google.com>
Reviewed-by: Armando Montanez <amontanez@google.com>
diff --git a/.gn b/.gn
index c46f2c8..362bede 100644
--- a/.gn
+++ b/.gn
@@ -25,5 +25,8 @@
     "mbedtls/include",
     "boringssl/src/include",
     "boringssl",
+
+    # Code generated by third-party tool.
+    "pw_tls_client/generate_test_data",
   ]
 }