roll: third_party/pigweed 9e4c976..2d273f8 (6 commits)

2d273f8:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/253513 docs: Add rustdocs to Bazel build
739cd50:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/253553 pw_bluetooth_proxy: Rename GetTxH4Packet to GetAclH4Packet
ce7b2d9:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/253595 pw_grpc: Allocate contiguous multibufs only
8b5abe6:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/253612 pw_bluetooth_proxy: Fix missing notify of queue space available
9720483:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/253554 pw_presubmit: Bazel lockfile check
5a62fe4:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/253332 blog: Shaping a better future for Bazel C/C++ toolchains

Rolled-Repo: https://pigweed.googlesource.com/pigweed/pigweed
Rolled-Commits: 9e4c976345d4d2..2d273f8599fd15
Roll-Count: 1
Roller-URL: https://cr-buildbucket.appspot.com/build/8728802340572980401
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I6193e494ab13e992772bb07efa3a1bc03b79992d
Reviewed-on: https://pigweed-review.googlesource.com/c/gonk/+/253707
Commit-Queue: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Bot-Commit: 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 9e4c976..2d273f8 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 9e4c976345d4d2de321e17853e9fb86493ff2200
+Subproject commit 2d273f8599fd15856bbb5fd2f9b60f97307879bd