Merge "Move is_system_uid utility from netd.c to netd.h" into main am: fe0d0f6e33 am: 23822baa12

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

Change-Id: I0d7f64c84eeb11f4b19a59cc27599a0d2dfc4bf7
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>