[PORT FROM R2] atomisp: (re)start ISP and handle frame buffers from ISR

[PORT FROM R2] atomisp: (re)start ISP and handle frame buffers from ISR

BZ: 17272

Atomisp driver needs to manage ISP and frame buffers in low latency way
to allow camera to work with high fps. This patch makes ISR to (re)start
ISP whenever it's possible and handle frame buffers.

Change-Id: I01b098937b9174a48bd97af216cb7b3c01b24c60
Orig-Change-Id: Id2bd9a7aa5dd4948350d442d72b9c1ca16cb0bb6
Signed-off-by: David Cohen <david.a.cohen@intel.com>
Reviewed-on: http://android.intel.com:8080/26723
Reviewed-by: Koski, Anttu <anttu.koski@intel.com>
Reviewed-by: Koskinen, Ilkka <ilkka.koskinen@intel.com>
Reviewed-by: Kruger, Jozef <jozef.kruger@intel.com>
Tested-by: Koski, Anttu <anttu.koski@intel.com>
Reviewed-by: buildbot <buildbot@intel.com>
Tested-by: buildbot <buildbot@intel.com>
Reviewed-on: http://android.intel.com:8080/28058
Reviewed-by: Tuominen, TeemuX <teemux.tuominen@intel.com>