roll: third_party/pigweed 3 commits

d55ec9627e60afd pw_bluetooth_sapphire: Use using aliases for Embos
dea5d4d8115fcd6 pw_bluetooth_sapphire: Add Bazel build files
8e469505d647384 pw_system: Add synchronization to pw::System alloc

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: a27a7371c69cb58..d55ec9627e60afd
Roller-URL: https://ci.chromium.org/b/8742563723475407953
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: If1f6f08057010549f9663f46aaf0445fa65c9d69
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/222858
Lint: Lint 🤖 <android-build-ayeaye@system.gserviceaccount.com>
Bot-Commit: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Commit-Queue: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
diff --git a/third_party/pigweed b/third_party/pigweed
index a27a737..d55ec96 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit a27a7371c69cb5820803be9ce842dd7242fb675a
+Subproject commit d55ec9627e60afd1d592a1bb1d93e8ce091d565b