roll: third_party/pigweed: rust: Register Pigweed Rust toolchains with bzlmod

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/231689

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: 00faa5bb544b18b..4816267a3988600
Roller-URL: https://ci.chromium.org/b/8737677265905784849
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I768767379ccebeb8b4d3af396701957e41c36d82
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/233978
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 00faa5b..4816267 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 00faa5bb544b18ba6dc267c34269d8a8cc4e5591
+Subproject commit 4816267a398860042a9c9eef4ebff2176281e43f