[Display]: Fix slideshow chaos issue after suspend/resume.

[Display]: Fix slideshow chaos issue after suspend/resume.

BZ: 29803

The default display mode is 32-bitBGRX. When play slideshow,
it will change to 16-bitBGRX mode. But when suspend, display driver
do not save the lastest DSPACNTR(0x70180) and DSPASTRIDE(0x70188) registers.
So in resume process, old values will be set into the registers.

Change-Id: I4699cd38d730e5323c86c0f5561e5d27469ebb6a
Signed-off-by: Pan Zhenjie <zhenjie.pan@intel.com>
Reviewed-on: http://android.intel.com:8080/41934
Reviewed-by: Shi, Yang A <yang.a.shi@intel.com>
Reviewed-by: Xu, Randy <randy.xu@intel.com>
Reviewed-by: Gross, Mark <mark.gross@intel.com>
Reviewed-by: Ai, Ke <ke.ai@intel.com>
Tested-by: Xu, Randy <randy.xu@intel.com>
Reviewed-by: buildbot <buildbot@intel.com>
Tested-by: buildbot <buildbot@intel.com>