[roll third_party/pigweed] pw_software_update: add update_helper and update_service

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/59544

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: ebf33b70f8fc2db..f463acd51147efa
Roller-URL: https://ci.chromium.org/b/8836078438919927345
Cq-Cl-Tag: roller-builder:pigweed-sample-project-roller
Cq-Cl-Tag: roller-bid:8836078438919927345
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: If70155ce20b75af473bb1166278197cb250e9a84
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/sample_project/+/60964
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 ebf33b7..f463acd 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit ebf33b70f8fc2db0d5561f5547bc9c2fac18f311
+Subproject commit f463acd51147efa06d4857be1ae0a7ea64aafc23