[roll third_party/pigweed] Fix: Include cstring in socket_stream.cc

Fix errors like:
  socket_stream.cc:62:23: error: ‘strerror’ is not a member of ‘std’

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/56900

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: 7a1878d7aa6f0af..e2bcc03c53eb628
Roller-URL: https://ci.chromium.org/b/8839003245990936177
Cq-Cl-Tag: roller-builder:pigweed-experimental-roller
Cq-Cl-Tag: roller-bid:8839003245990936177
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I1e43c953980df3cac9fea4775a9241b40c306bc9
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/56987
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 7a1878d..e2bcc03 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 7a1878d7aa6f0af429da71e5fabcc16adf60f630
+Subproject commit e2bcc03c53eb628a0bd1855cd629ac59ecfe6e7e