[roll third_party/pigweed] pw_software_update: Add gn switch for verification

Certain pigweed downstream projects and builders are experiencing ram
space shortage issues and not able to integrate bundle verification
logic. This CL adds a gn switch to allow compiling out the verification
code. This is a temporary solution for smooth integration of the
verfication code for these projects. This switch should immediately be
removed after all downstream projects sort out enough ram space.

Original-Bug: 456
Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/68093

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: f228b41839edb40..a1d6cd641276fe1
Roller-URL: https://ci.chromium.org/b/8828193708189884785
Cq-Cl-Tag: roller-builder:pigweed-sample-project-roller
Cq-Cl-Tag: roller-bid:8828193708189884785
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I45de6ad96002f4c07676ece0dd800091c540c5f8
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/sample_project/+/73542
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 f228b41..a1d6cd6 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit f228b41839edb40b8b3ffda3516c7144fd2626b6
+Subproject commit a1d6cd641276fe172249e4e15069daef6dc5a8ac