[roll third_party/pigweed] pw_trace_tokenized: Allow event callback to modify event

Change the event callback API to accept a pointer to
pw_trace_tokenized_TraceEvent, and move the event callback to before
inserting in the queue. This allows the platform to implement a callback
to modify run-time fields in the trace event.

Add example where the callback modifies the trace_id field to store the
Linux info, used for auto grouping trace events by tid.

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/126310

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: 35c0f029b35ab92..5133ef1ba4de374
Roller-URL: https://ci.chromium.org/b/8791511459807269153
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I165b28d367edcbe99822e4f2c7701dc89738697e
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/126746
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 35c0f02..5133ef1 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 35c0f029b35ab92e13d79bbca87e2f26acc2c4ed
+Subproject commit 5133ef1ba4de37428a440b147dfd321487e33c64