sdm: Add support for HDMI minimum HDCP encryption level change.

- Enable HDCP libraries to communicate with SDM via a qdutils API to
  indicate change in encryption level.
- Write this change on HDMI file node to trigger driver.

Change-Id: I226d4e986081b97243c80ea30c16b05ea34499c4
diff --git a/libqservice/IQService.h b/libqservice/IQService.h
index 4c0271a..df8e235 100644
--- a/libqservice/IQService.h
+++ b/libqservice/IQService.h
@@ -70,6 +70,7 @@
         GET_DISPLAY_ATTRIBUTES_FOR_CONFIG = 28, //Get attr for specified config
         SET_DISPLAY_MODE = 29, // Set display mode to command or video mode
         SET_CAMERA_STATUS = 30, // To notify display when camera is on and off
+        MIN_HDCP_ENCRYPTION_LEVEL_CHANGED = 31,
         COMMAND_LIST_END = 400,
     };