sdm: Implement idle fallback support in DRM.

Add CRTC property to set idle timeout. Enhance DRM event
handler for idle fall back custom event registration and
event handling

CRs-Fixed: 2097588

Change-Id: I543286a59a4ae95bc32b25960d1fc43551391951
diff --git a/libdrmutils/drm_interface.h b/libdrmutils/drm_interface.h
index f40f324..53a709e 100644
--- a/libdrmutils/drm_interface.h
+++ b/libdrmutils/drm_interface.h
@@ -242,6 +242,12 @@
    */
   CRTC_SET_SOLIDFILL_STAGES,
   /*
+   * Op: Sets idle timeout.
+   * Arg: uint32_t - CRTC ID
+   *      uint32_t - idle timeout in ms
+   */
+  CRTC_SET_IDLE_TIMEOUT,
+  /*
    * Op: Returns retire fence for this commit. Should be called after Commit() on
    * DRMAtomicReqInterface.
    * Arg: uint32_t - Connector ID