roll: third_party/pigweed e6a6bcc..ecdd75e (7 commits)

ecdd75e:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/390473 pw_rpc: Fix implicit conversion warnings
f7cae80:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/295773 pw_persistent_ram: Rework docs, add diagram
368c08f:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/389754 pw_string: Small docs fixes
1bed093:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/389753 pw_allocator: Small docs fixes
f5d65bf:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/387057 pw_build: Avoid running pw through bazel unless stale
9d20141:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/390092 agents: Add kernel testing skill
da331a4:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/388092 pw_rpc_transport: Fix implicit conversion warnings

Rolled-Repo: https://pigweed.googlesource.com/pigweed/pigweed
Rolled-Commits: e6a6bcc12dc009..ecdd75e8516cf4
Roll-Count: 1
Roller-URL: https://cr-buildbucket.appspot.com/build/8686229471865410593
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: If57f048f79ccbf4ff45f36ea03198a8a18cb0a2f
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/examples/+/390652
diff --git a/third_party/pigweed b/third_party/pigweed
index e6a6bcc..ecdd75e 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit e6a6bcc12dc0096feace2be1d08e9d002d6e8aea
+Subproject commit ecdd75e8516cf4f441c9a1534f6adb515ffe906c