[roll third_party/pigweed] docs: Add changelog

Original-Bug: b/292247409
Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/160170

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: abf8be3fea71793..a57b05587b88860
Roller-URL: https://ci.chromium.org/b/8774011736584610545
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I4db270ed8953237f43cf7db996869aa5d556495f
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/161750
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 abf8be3..a57b055 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit abf8be3fea71793c1c85820cec335be7ca90c4d1
+Subproject commit a57b05587b88860f915f43bd9616dbd20d7757ba