Fix null pointer crash in AIDL radio HAL VTS am: cf892db1ef am: e065f848d0 am: 050c07c475

Original change: https://googleplex-android-review.googlesource.com/c/platform/hardware/interfaces/+/24133137

Change-Id: I52e0a5a66e613108fc60371cb382f3713b34f1b2
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>