[roll third_party/pigweed] pw_thread: Move protos to pw.thread.proto

Moves pw_thread proto files into the pw.thread.proto package to avoid
naming collisions with non-proto types provided by the module.

Original-Requires: pigweed-internal:32463
Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/112115

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: bc8a2633c33ebfc..bcf38c3a86fb97b
Roller-URL: https://ci.chromium.org/b/8801760694339526017
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I932a0fd4ca1ed4898049518d440635cfa9825991
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/112431
Bot-Commit: Pigweed Integration Roller <pigweed-integration-roller@pigweed.google.com.iam.gserviceaccount.com>
Commit-Queue: Pigweed Integration Roller <pigweed-integration-roller@pigweed.google.com.iam.gserviceaccount.com>
diff --git a/third_party/pigweed b/third_party/pigweed
index bc8a263..bcf38c3 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit bc8a2633c33ebfcb5895a73f3ba213b1faf845f8
+Subproject commit bcf38c3a86fb97bcb825e8ab7ea91fe3ea6180e2