roll: third_party/pigweed 947b968..a9c9b55 (4 commits)

a9c9b55:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/287652 pw_numeric: Saturating multiplication polyfill
8fc7b53:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/287713 pw_kernel: Factor thread structures into module
80b61fe:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/281892 pw_bluetooth_sapphire: Don't offload non-offloadable filters
9b059bf:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/288654 roll: buildifier

Rolled-Repo: https://pigweed.googlesource.com/pigweed/pigweed
Rolled-Commits: 947b9681400b8b..a9c9b55ecde6d6
Roll-Count: 1
Roller-URL: https://cr-buildbucket.appspot.com/build/8715685412791758481
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I1fc14a5966f148248788f116516f5dab7c40773a
Reviewed-on: https://pigweed-review.googlesource.com/c/gonk/+/288992
Commit-Queue: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Lint: Lint 🤖 <android-build-ayeaye@system.gserviceaccount.com>
Bot-Commit: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
diff --git a/third_party/pigweed b/third_party/pigweed
index 947b968..a9c9b55 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 947b9681400b8ba5f0af01995354eeb06b393747
+Subproject commit a9c9b55ecde6d6b53416cea179c83c4d0e868da3