[media] atomisp: drop unused qos variable

Fixes a sparse warning:

drivers/staging/media/atomisp/platform/intel-mid/intel_mid_pcihelpers.c:35:5: warning: symbol 'qos' was not declared. Should it be static?

Signed-off-by: Valentin Vidic <Valentin.Vidic@CARNet.hr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>