roll: third_party/pigweed 2d273f8..97a16b0 (5 commits)

97a16b0:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/254113 bazel: Remove the unused attribute _cc_toolchains
7e8ef36:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/254115 docs: Update changelog
c80d2e1:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/253953 pw_presubmit: Add diff_upstream_python_constraints
0e6dc34:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/253516 pw_bluetooth_proxy: Wrap PopulateTxL2capPacket over PopulateL2capPacket
e760271:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/253858 docs: Improve Bazel lockfile docs

Rolled-Repo: https://pigweed.googlesource.com/pigweed/pigweed
Rolled-Commits: 2d273f8599fd15..97a16b0afe5591
Roll-Count: 1
Roller-URL: https://cr-buildbucket.appspot.com/build/8728721366334690001
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: Ib0728d65a48268e429b522702167c9961a053286
Reviewed-on: https://pigweed-review.googlesource.com/c/gonk/+/254153
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 2d273f8..97a16b0 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 2d273f8599fd15856bbb5fd2f9b60f97307879bd
+Subproject commit 97a16b0afe5591afdb904c5b07e2062e9ae4385f