pvmfw: DRY vcpufreq error path & prevent panic am: 8ba89801e0

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Virtualization/+/2963846

Change-Id: Ib21d925caed37e6d63a4523f0116dd80b65c176a
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>