[roll third_party/pigweed] pw_doctor: Don't require bazel

Original-Bug: 392
Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/47840

third_party/pigweed Rolled-Commits: 8bbc213e8b763ab..8a06bc6fc38c421
Roller-URL: https://ci.chromium.org/b/8845405463052652784
Cq-Cl-Tag: roller-builder:pigweed-experimental-roller
Cq-Cl-Tag: roller-bid:8845405463052652784
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: Ide0e83d85c5c817517e179af20c2652732bd2e9f
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/47801
Reviewed-by: 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 8bbc213..8a06bc6 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 8bbc213e8b763abd64de8093e42b6ed6c8e5fa9e
+Subproject commit 8a06bc6fc38c42185a517e805e592a509c2b6ea5