sdm: Add support for HWC with no display HW

-If there is no display HW, create a dummy
 display in HWC. Do not send error to SF.
 Route all incoming call from SF to dummy
 display in HWC.

Change-Id: I08b8dc4b277421dce2e12c7dc5878c05909aa9b7
CRs-Fixed: 2449460
3 files changed