roll: third_party/pigweed: pw_sync: [[nodiscard]] for try_lock() and similar functions

Ignoring the return value of a try_lock() function could be a serious
issue.

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/229311

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: 8d8bb25577cd054..2a34a2865e92cf7
Roller-URL: https://ci.chromium.org/b/8738422496076076273
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: Ifdc459e2f1ffa1aa8b9881fd73409a89a6120bc8
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/examples/+/232102
Bot-Commit: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Commit-Queue: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Lint: Lint 🤖 <android-build-ayeaye@system.gserviceaccount.com>
diff --git a/third_party/pigweed b/third_party/pigweed
index 8d8bb25..2a34a28 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 8d8bb25577cd0541b89db8a2771d1280679c1455
+Subproject commit 2a34a2865e92cf70c67186ef701882d27d8604d8