[roll third_party/pigweed] pw_toolchain: Remove stale comment

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/60183

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: 24a4cc0f860aeca..49d489d4c2b318a
Roller-URL: https://ci.chromium.org/b/8836632430718477489
Cq-Cl-Tag: roller-builder:pigweed-sample-project-roller
Cq-Cl-Tag: roller-bid:8836632430718477489
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: Ide0993a54e262efccfcc1531026b41c2af92632f
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/sample_project/+/60220
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 24a4cc0..49d489d 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 24a4cc0f860aeca152a8eb591276c9063b6798f9
+Subproject commit 49d489d4c2b318aae51eae6be299ce69502fffc8