Camera: Fix offline session close locking

The HIDL/AIDL session close is expected to trigger processCaptureResult
callbacks. Currently both methods will try to acquire the same
'mLock' which can result in a potential deadlock.
Revert back to the previous locking scheme where session close and
release are synchronized via 'mInterfaceLock' and 'mLock'
respectively.
Additionally handle failing offline client registration by
ensuring that the client is initialized before it gets released.
This will allow CameraHals to return/fail any pending offline
requests.

Bug: 267723307
Test: Camera CTS

Change-Id: Ib55d654bfa213ec2df0fc4590017f77c4492b28e