[third_party/pigweed] Roll 2 commits

38fee79685436e1 pw_software_update: Verify targets metadata
b175a422d0100ea pw_toolchain: Add Cortex-M0+ clang toolchain

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: 9fb75ff2f75b10c..38fee79685436e1
Roller-URL: https://ci.chromium.org/b/8827936835057786353
Cq-Cl-Tag: roller-builder:pigweed-sample-project-roller
Cq-Cl-Tag: roller-bid:8827936835057786353
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I7c4b1632040967a94c7e3489e29f4c492ecaaf58
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/sample_project/+/73920
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 9fb75ff..38fee79 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 9fb75ff2f75b10c109417834240ad54f62fd6ccc
+Subproject commit 38fee79685436e1b2e0d69919150e639b57d1dd7