Check HIDL ICallback return values in sample drivers

If a Return<T> containing a transport error is not checked (isOk())
before it is destroyed, the application will be terminated with a HIDL
error. This CL checks all HIDL return values with isOk() in the driver,
and logs any appropriate message.

Bug: 118636733
Test: mma
Test: NeuralNetworksTest_static (with sample drivers)
Change-Id: I9b2547b7a6a76bd2c97f535ae55c38725dc6aed9
1 file changed