[roll third_party/pigweed] pw_snapshot: Add RISCV CpuArchitecture to metadata

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/185630

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: cf6b92b217407ce..c06726f2ad32df7
Roller-URL: https://ci.chromium.org/b/8761245941034949729
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I85a1204e46308b795f057391de128dc147252f94
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/185670
Commit-Queue: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Bot-Commit: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
diff --git a/third_party/pigweed b/third_party/pigweed
index cf6b92b..c06726f 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit cf6b92b217407cef85824e3881542d65d0109867
+Subproject commit c06726f2ad32df7661db30c40a2880e02d5d2ef2