[third_party/pigweed] Roll 2 commits

d54f6c446cd85ec mbedtls: Avoid the use of unsupported libc functio
c3dfc3987262a43 pw_bluetooth_sapphire: Stub bt-host CIPD manifest

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: bab24b648730fc3..d54f6c446cd85ec
Roller-URL: https://ci.chromium.org/b/8751635273908818177
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: Ic9097f063b5adbf36278a4d9e57f11f2ef618732
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/201811
Bot-Commit: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Commit-Queue: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
diff --git a/third_party/pigweed b/third_party/pigweed
index bab24b6..d54f6c4 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit bab24b648730fc354751b13192c0a254c64b0ca3
+Subproject commit d54f6c446cd85ec00d75018b2e8187f15aa09eb3