sdm: Implement getDisplayIdentificationData

* Implement call flow from client to display interface.

* Use display interface to query EDID blob from Connector information
  and return to client alongside pre-established port information from
  sde-drm during display creation.

* Create EDID blob for Null Display (QMAA) to represent a 1920x1080
  60fps display with panel name "Null Display" and port corresponding to
  either builtin or external, depending on DisplayNull class instantiated.

* Introduce kErrorDriverData as a display interface error to represent
  situations in which expected data from the driver is missing.
  Currently this applied to EDID blob for all physical panels.

* Update UnregisterDisplay API to allow cleanup of token via sde-drm.

Change-Id: I5661f7bc0a5a68cdffa0cad3fe2351baa647012c
CRs-Fixed: 2380873
19 files changed