[third_party/pigweed] Roll 2 commits

c2915194debfc14 pw_toolchain: Add manual tag to Rust toolchains
eb97b4508f6e0ca rp2040: Add upstream Bazel platform definition

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: c932087017d7024..c2915194debfc14
Roller-URL: https://ci.chromium.org/b/8746660972102187265
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I0019f86f0de56a0d32fa85f379482c413da11f91
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/211937
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 c932087..c291519 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit c932087017d7024f2b57be920ce692349be4d65a
+Subproject commit c2915194debfc1471944672afb8738896cc483ff