mm-video: vidc:  release registered buffers from driver

- In some scenarios, component may restart from loaded to idle
  state in the same context and it is resulting in the preapare
  buf failure as previous buffers are not unregistered. Unregister
  the buffers from driver while stopping the component.

Change-Id: I048cf715d2e83b05df99eaf10776cff0bbb2acd2
1 file changed