roll: third_party/pigweed: third_party/pigweed: Fix license declaration to make copybara happy

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/235158
Docs-Not-Needed: Erik Gilling <konkers@google.com>

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: 7632a0fdc0fc1a2..7d9c604f73e8436
Roller-URL: https://ci.chromium.org/b/8737055894677927153
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I898e6f9d0a14ef024c01a26a9ba831d9e7e55a60
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/examples/+/235176
Bot-Commit: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Commit-Queue: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Lint: Lint 🤖 <android-build-ayeaye@system.gserviceaccount.com>
diff --git a/third_party/pigweed b/third_party/pigweed
index 7632a0f..7d9c604 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 7632a0fdc0fc1a2dd4b23e82e127931ac2ef7fd7
+Subproject commit 7d9c604f73e84369e33121e06b7a2c26b41eb57b