sde: hwc_display: Set all the display attributes

- Set the HWC_DISPLAY_SECURE attribute in the HWC.
- All the physical connected displays are assumed to be secure by SF.
  Hence set this display attribute as true.
- This is added for backcompatibility.

Change-Id: I9e0ac4f3d923f990a5c81a3c36638bd62fdc83c0

displayengine/libs/hwc/hwc_display.cpp

@@ -125,6 +125,9 @@ int HWCDisplay::GetDisplayAttributes(uint32_t config, const uint32_t *attributes
     case HWC_DISPLAY_DPI_Y:
       values[i] = INT32(variable_config.y_dpi * 1000.0f);
       break;
+    case HWC_DISPLAY_SECURE:
+      values[i] = INT32(true); // For backward compatibility. All Physical displays are secure
+      break;
     default:
       DLOGE("Spurious attribute type %d", attributes[i]);
       return -EINVAL;