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

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

Change-Id: I2d99e065abdf4e44b5104c394dc22ef316c96137
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>