roll: third_party/pigweed pw_build: Break apart pigweed.bzl

Overtime, Pigweed unintentionally grew a `pigweed.bzl` file that ended
up being a grab-bag of various Bazel rules. This change breaks up this
file to mirror GN by moving rules into their own individual files,
moving to different modules where appropriate.

Original-Bug: b/370792896
Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/239133
Original-Revision: 53b16cd8d2907855b13bec9159286927de602a72

Rolled-Repo: https://pigweed.googlesource.com/pigweed/pigweed
Rolled-Commits: 547e0582fa65c3..53b16cd8d29078
Roller-URL: https://ci.chromium.org/b/8735149254612241441
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I06f91fb8066f9971a776091fd5f65aeedc864fc4
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/examples/+/239632
Commit-Queue: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Lint: Lint 🤖 <android-build-ayeaye@system.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 547e058..53b16cd 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 547e0582fa65c376af36d0186f4d94a33badc9e3
+Subproject commit 53b16cd8d2907855b13bec9159286927de602a72