HDMI-Audio: Update process_trigger flag to valid HAD state.

HDMI-Audio: Update process_trigger flag to valid HAD state.

BZ: 24898 24987

During Dummy playback, statement to modifyprocess_trigger flag
is missing. This moves HAD to invalid state in some cases.

The solution is to modify process_trigger flag to valid HAD state.
HAD state is also updated with DISCONNECT, when the device is absent
and prepare is called.

Includes HDMI Klocwork spinlock error correction.

Change-Id: I17f272cca392e329b34ceb595d6fd7f4cfbc9586
Signed-off-by: Vaibhav Agarwal <vaibhav.agarwal@intel.com>
Signed-off-by: Shreyas Neerebailoor <shreyasx.neerebailoor@intel.com>
Reviewed-on: http://android.intel.com:8080/36842
Reviewed-by: Vinnakota, Lakshmi N <lakshmi.n.vinnakota@intel.com>
Reviewed-by: Gupta, ArvindX K <arvindx.k.gupta@intel.com>
Reviewed-by: Hibare, PramodX <pramodx.hibare@intel.com>
Tested-by: Hibare, PramodX <pramodx.hibare@intel.com>
Reviewed-by: buildbot <buildbot@intel.com>
Tested-by: buildbot <buildbot@intel.com>