atomisp: porting driver R2 fix-patches

atomisp: porting driver R2 fix-patches

BZ: 17272

Forward ported patch from r2-stable starts to threat warnings as errors
f271944ad8bcad5c4cbbd5b3a99f50f452da56b8 atomisp: remove compiler warnings

Cannot enable -Werror while tng disabled, see known issue:
27390f90d76fcce1cc59eb64b080e43237079163 atomisp: porting driver

Change-Id: I89c11f7c0b6918d356a367960b46094d96a6ad12
Signed-off-by: Teemu Tuominen <teemux.tuominen@intel.com>
Reviewed-on: http://android.intel.com:8080/28028
Reviewed-by: Koski, Anttu <anttu.koski@intel.com>
Tested-by: Koski, Anttu <anttu.koski@intel.com>
Reviewed-by: buildbot <buildbot@intel.com>
Tested-by: buildbot <buildbot@intel.com>