roll: third_party/pigweed a4549e5..9687a0c (6 commits)

9687a0c:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/269992 pw_async2: Size optimizations for PendFuncAwaitable
1bc28ab:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/268933 pw_build: Remove deprecated CMake function
62d8518:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/269993 pigweed.json: Add separate sanitizer Bazel programs
2788c69:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/264012 pw_crypto: Use pw::span_cast
0101b0e:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/269194 pw_allocator: Enable size reports in Bazel
4fe911e:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/261152 pw_build_mcuxpresso: Add flag to clean old files

Rolled-Repo: https://pigweed.googlesource.com/pigweed/pigweed
Rolled-Commits: a4549e53fd52b2..9687a0cdc51bdd
Roll-Count: 1
Roller-URL: https://cr-buildbucket.appspot.com/build/8722286845549701233
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I035e46ce6a672756ee088af46ab2df38c2317d12
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/examples/+/270332
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 a4549e5..9687a0c 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit a4549e53fd52b28b3698e98025b6b1fca0318d60
+Subproject commit 9687a0cdc51bdd1e899bbc50c857a9fac6f3e641