[roll pigweed] pw_tokenizer: Make pw_span dep public since it is used in a header

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/100460

https://pigweed.googlesource.com/pigweed/pigweed
pigweed Rolled-Commits: f6df36c81ed3669..d6caac16b883a53
Roller-URL: https://ci.chromium.org/b/8809976044231836817
Cq-Cl-Tag: roller-builder:pigweed-zephyr-roller
Cq-Cl-Tag: roller-bid:8809976044231836817
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I7e12c4ae9520d74bf91f87c8a4f52476987e022c
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/zephyr-integration/+/100501
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 f6df36c..d6caac1 160000
--- a/pigweed
+++ b/pigweed
@@ -1 +1 @@
-Subproject commit f6df36c81ed3669a100336e4af5ce8be247d8518
+Subproject commit d6caac16b883a53dc9ad86ddccd840178ce0588c