[roll third_party/pigweed] third_party/boringssl: Remove crypto_sysrand.cc

Remove crypto_sysrand.cc from boringssl target. This file
added test stubs and is no longer necessary. This fixes
a linker bug where the read() syscall in googletest is linked
to this stub, resulting in death test failures.

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/175017

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: 696953b917527ba..4a068f79e329cf6
Roller-URL: https://ci.chromium.org/b/8767053676905564033
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: Ifa58b453f0b5a31dc527e5f11e9b9e152b576e83
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/176120
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 696953b..4a068f7 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 696953b917527ba876e9372ffc2a94c47bb4ce5b
+Subproject commit 4a068f79e329cf64bd8ae812659c0d81fa04fa4e