[roll pigweed] pw_build: Add pw_build_DEFAULT_VISIBILITY

Adds a flag for controlling the default visibility of pw_* C/C++
targets to support allow-listing of Pigweed modules.

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/102920

https://pigweed.googlesource.com/pigweed/pigweed
pigweed Rolled-Commits: f89426038c046b7..7e9a8db46b93aaa
Roller-URL: https://ci.chromium.org/b/8807375788571961457
Cq-Cl-Tag: roller-builder:pigweed-zephyr-roller
Cq-Cl-Tag: roller-bid:8807375788571961457
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I769c51332a91634b370cb6e985d6f552ff48a285
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/zephyr-integration/+/103784
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/pigweed b/pigweed
index f894260..7e9a8db 160000
--- a/pigweed
+++ b/pigweed
@@ -1 +1 @@
-Subproject commit f89426038c046b78364924bd9ae9ef160948878d
+Subproject commit 7e9a8db46b93aaa787c664ac750fbd57247430ec