[roll third_party/pigweed] pw_status: Adopt latest docs standard

First step towards bringing pw_status docs up to our latest standard.
Some parts of pw_status are not yet documented with Doxygen (e.g.
StatusWithSize), but that can come in future CLs.

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/181181

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: ab02795c6850a9a..77c17e6d2a505bf
Roller-URL: https://ci.chromium.org/b/8764147865600781921
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I1308f216eccbc28ec523cadea8ca6fab357a141e
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/181383
Commit-Queue: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Bot-Commit: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
diff --git a/third_party/pigweed b/third_party/pigweed
index ab02795..77c17e6 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit ab02795c6850a9a69dcb2f447874802f1f0ec413
+Subproject commit 77c17e6d2a505bfa4743568940f12eca47875bfb