Add hostapd_test_utils helper methods for the am: 3454ce179a

Original change: https://googleplex-android-review.googlesource.com/c/platform/hardware/interfaces/+/24589589

Change-Id: Ie5e88b46753ff38f58c9c5b4b66d8e71d268c1c1
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>