roll: third_party/pigweed roll: clang, rust

clang:

From git_revision:553da9634dc4bae215e6c850d2de3186d09f9da5
To git_revision:03b0f55d9c6319a851a60bb084faca0e32a38f2b

rust:

From rust_revision:77a455303bf08da8eef6236b2b4422a77cd25c42
To rust_revision:afa859f8121bf2985362a2c8414dc71a825ccf2d

with matching llvm_revision:03b0f55d9c6319a851a60bb084faca0e32a38f2b

Pulled in via new combined git_revisions tag.

Original-Bug: 411404476
Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/284552
Tests-Not-Needed: Austin Foxley <afoxley@google.com>
Presubmit-Verified: CQ Bot Account <pigweed-scoped@luci-project-accounts.iam.gserviceaccount.com>
Original-Revision: e38aff6439df47af515a4cb5554d4925e1621f67

Rolled-Repo: https://pigweed.googlesource.com/pigweed/pigweed
Rolled-Commits: ef778d436b0e8d..e38aff6439df47
Roll-Count: 1
Roller-URL: https://cr-buildbucket.appspot.com/build/8716867015923397889
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I9086c58453fccfdb4319567a9fdadb38e7187027
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/285712
Bot-Commit: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Commit-Queue: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
diff --git a/third_party/pigweed b/third_party/pigweed
index ef778d4..e38aff6 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit ef778d436b0e8deda48bb337d65186e5f1c42ea3
+Subproject commit e38aff6439df47af515a4cb5554d4925e1621f67