audioserver: return binder call permission error in reply

When a transaction to IAudioFlinger or IAudioPolicyService is detected
from an unauthorized source, return the INVALID_OPERATION status in
reply Parcel and not as transaction status.

Also removed check on SET_RINGER_MODE as it is not implemented on client
side and allow SET_MODE from system AIDs instead of just audioserver.

Bug: 78615605
Test: manual audio smoke tests.
Change-Id: Ia4fdfc22f049da69aaa9d45075e1c502eecf4521