[third_party/pigweed] Roll 2 commits

7588aed88bc61d1 pw_thread_sync_freertos: Add explicit casts
cf1c02052f5c7d6 pw_system: Add pw_starter_target template

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: a463f7d569df89a..7588aed88bc61d1
Roller-URL: https://ci.chromium.org/b/8827907258852547297
Cq-Cl-Tag: roller-builder:pigweed-sample-project-roller
Cq-Cl-Tag: roller-bid:8827907258852547297
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: Idfcb8562e5a18d1116726eae43aa111194529ee1
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/sample_project/+/74042
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 a463f7d..7588aed 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit a463f7d569df89a1e59f62d7d0bd454cba4c4f5c
+Subproject commit 7588aed88bc61d1dda71ce5c9c922fa2d6a002d6