[roll third_party/pigweed] third_party/fuchsia: Add stdcompat/functional.h

Add sdk/lib/stdcompat/include/lib/stdcompat/functional.h to Fuchsia
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Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/126694

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: e3d96d371649fcc..809a423d7ddf0d2
Roller-URL: https://ci.chromium.org/b/8791413571455307585
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: Ie27180cb474e64f96497dce18cf7414806aa9370
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/126793
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 e3d96d3..809a423 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit e3d96d371649fcc38477fc27a7ede5b686f83f0a
+Subproject commit 809a423d7ddf0d288718050f7ec3e18fff477e78