[PORT FROM R2] atomisp: ISR and workqueue are out of sync

[PORT FROM R2] atomisp: ISR and workqueue are out of sync

BZ: 17272

Atomisp's ISR sets isp->irq_infos everytime an interrupt happens
overwritting previous value. If workqueue didn't have time to check
previous interrupt, the driver will ignore it. This patch fixes this
issue.

Change-Id: Ie905e5dbc924c187f9c47bdffc70ae6a3443080a
Orig-Change-Id: I1706ada8ef53ec4d447cd184c7a232a7cb96e3ab
Signed-off-by: David Cohen <david.a.cohen@intel.com>
Reviewed-on: http://android.intel.com:8080/23195
Reviewed-by: Wang, Wen W <wen.w.wang@intel.com>
Reviewed-by: Koski, Anttu <anttu.koski@intel.com>
Tested-by: Koski, Anttu <anttu.koski@intel.com>
Reviewed-by: Koskinen, Ilkka <ilkka.koskinen@intel.com>
Reviewed-by: buildbot <buildbot@intel.com>
Tested-by: buildbot <buildbot@intel.com>
Reviewed-on: http://android.intel.com:8080/27994
Reviewed-by: Tuominen, TeemuX <teemux.tuominen@intel.com>