Merge "init: Combine two global sigchld_fd variables into one" into main am:...

Merge "init: Combine two global sigchld_fd variables into one" into main am: 142f8129 am: ba881778

Original change: https://android-review.googlesource.com/c/platform/system/core/+/2834996



Change-Id: Ia9f0e9abde2482f3f830f356c96812ea8a37e3aa
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>