Merge "Move is_system_uid utility from netd.c to netd.h" into main am: fe0d0f6e33 am: f5e896d25c

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/2808573

Change-Id: Id15fd2df3a3fac6c9e5f18f4179f2543f7be0128
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>