drm_hwcomposer: Add FENCE_OUT_PTR property to DrmCrtc

Add support for handling the FENCE_OUT_PTR property to DrmCrtc

Signed-off-by: Robert Foss <robert.foss@collabora.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
diff --git a/drmcrtc.h b/drmcrtc.h
index ad95352..2e8c811 100644
--- a/drmcrtc.h
+++ b/drmcrtc.h
@@ -45,6 +45,7 @@
 
   const DrmProperty &active_property() const;
   const DrmProperty &mode_property() const;
+  const DrmProperty &out_fence_ptr_property() const;
 
  private:
   DrmResources *drm_;
@@ -63,6 +64,7 @@
 
   DrmProperty active_property_;
   DrmProperty mode_property_;
+  DrmProperty out_fence_ptr_property_;
 };
 }