ExternalCameraHAL: improve buffer and error handling

After enabling HALL Buffer Management, it requires more careful
error handling and syncing. Process the buffer request error correctly.
Handle the lock and states correctly.

Bug: 299182874
Test: CTS passed, expecially
./cts-tradefed run cts -m CtsCameraTestCases -t android.hardware.camera2.cts.NativeCameraDeviceTest
./cts-tradefed run cts -m CtsCameraTestCases -t android.hardware.camera2.cts.RobustnessTest

Merged-in: I04d8e19a2ee78580e54340378122c724a3de8edb
Change-Id: I04d8e19a2ee78580e54340378122c724a3de8edb