CameraHal: Avoids possible race conditions while accessing 'mParams'

- Direct access of 'mParams' outside of 'get-/setParameters()' should
  be avoided. The underlying strings can get invalidated with each
  call to 'setParameters()', which can lead to instabilities.
- This change also removes legacy stereo code, which is not used
  any more.

Bug: 6509329

Change-Id: Ief6df206c33fbdc666644cea8630e0bce6a36c00
Signed-off-by: Emilian Peev <epeev@mm-sol.com>
7 files changed