[roll third_party/pigweed] pw_software_update: Remove landing switch

Now that the ram space issue in downstream projects have been resolved.
We can remove the landing compilation switch upstream.

Original-Bug: 456
Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/74580

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: 67af12f85815e84..afa5137a10438b0
Roller-URL: https://ci.chromium.org/b/8827745541220169889
Cq-Cl-Tag: roller-builder:pigweed-sample-project-roller
Cq-Cl-Tag: roller-bid:8827745541220169889
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I9910431e2148893d884595d95462c86a7fa2fa93
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/sample_project/+/74723
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 67af12f..afa5137 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 67af12f85815e84a219e5d5d131b6a5c8c8a58eb
+Subproject commit afa5137a10438b0e9ae34e49b750d8e3847f1fd9