[roll third_party/pigweed] pw_build: Cover more modules with Soong

Adds Android blueprint files for the following modules:
- pw_bytes
- pw_preprocessor
- pw_polyfill
- pw_span
- pw_tokenizer
- pw_varint

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/98268

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: 1c974a121a9c7eb..fa778efaf7764ce
Roller-URL: https://ci.chromium.org/b/8810441322102972833
Cq-Cl-Tag: roller-builder:pigweed-experimental-roller
Cq-Cl-Tag: roller-bid:8810441322102972833
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I280f532beb658df6fe118fa422c22f8cd11043b3
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/99803
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 1c974a1..fa778ef 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 1c974a121a9c7eb0694407ba5aae13fbe410bbf5
+Subproject commit fa778efaf7764ce4dcde487328358606d07b4b08