display: Add interface to support Early Wake-up

Add interface to support Early Wake-up notification feature.

CRs-Fixed: 2727498
Change-Id: I888a953f48c4ffb445d7309f8590ae23258164b7
diff --git a/include/display_extn_intf.h b/include/display_extn_intf.h
index 84cd508..ac79cd8 100644
--- a/include/display_extn_intf.h
+++ b/include/display_extn_intf.h
@@ -35,6 +35,12 @@
 class DisplayExtnIntf {
  public:
   virtual int SetContentFps(uint32_t fps) = 0;
+  virtual void RegisterDisplay(uint32_t display_id) = 0;
+  virtual void UnregisterDisplay(uint32_t display_id) = 0;
+  virtual int SetActiveConfig(uint32_t display_id, uint32_t config_id) = 0;
+  virtual int NotifyEarlyWakeUp(bool gpu, bool display) = 0;
+  virtual int NotifyDisplayEarlyWakeUp(uint32_t display_id) = 0;
+
  protected:
   virtual ~DisplayExtnIntf() { }
 };