[third_party/pigweed] Roll 2 commits

e6aa95bf08fba2b pw_env_setup: Pin pip and pip-tools
f3190dcd2b5a44c pw_arduino_build: STM32 Core fixes

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: aac7fab8fbb8d1f..e6aa95bf08fba2b
Roller-URL: https://ci.chromium.org/b/8766228295079721761
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I4238539c746c875f941106a26bda6c3b734ef4d8
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/kudzu/+/177837
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 aac7fab..e6aa95b 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit aac7fab8fbb8d1f88dea84bda6d3acaf74add84e
+Subproject commit e6aa95bf08fba2bd9120b61d94e77d4d2b60c721