Interpret STATUS_UNKNOWN_TRANSACTION as a unsupported vibrator result

The AIDL versioning documentation says this is the exception code
returned by older versions that do not implement the methods:
https://source.android.com/devices/architecture/aidl/stable-aidl#versioning-interfaces

Update the vibrator::HalResult for this exception code to be
unsupported, which will prevent the service from retrying this operation
on that device.

Bug: 190526054
Test: libvibratorservice_test
Change-Id: Ifdc9c02431ec7c3ad3fd54b62049e15766f6a5a1