[roll third_party/pigweed] pw_format: Add initial support for untyped specifiers

* Introduces a %v format specifier for untyped data arguments.
* For stable toolchains arguments must be annotated with their
  type using `value as type`.
* Future support for the experimental feature `type-alias-impl-trait`
  will allow arguments to not be annotated.
* Currently only i32 and u32 arguments are supported to keep this
  patch small.
* pw_log_backend_println, pw_log_backend_printf, and pw_tokenizer
  are updated to work with the new APIs.

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/187650

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: 04b24a89a24be81..6ac2d4b370be1ee
Roller-URL: https://ci.chromium.org/b/8753527516784716465
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: Id35f48d4a8fec966bb8b302cc0d8e044cf7edc48
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/196391
Commit-Queue: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.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 04b24a8..6ac2d4b 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 04b24a89a24be81cd8ffac1df6e784f28d9e24bd
+Subproject commit 6ac2d4b370be1eef6bbc1fa0b5951fc60df04af9