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.cpp b/drmcrtc.cpp
index 1fbdc12..c139869 100644
--- a/drmcrtc.cpp
+++ b/drmcrtc.cpp
@@ -51,6 +51,12 @@
     ALOGE("Failed to get MODE_ID property");
     return ret;
   }
+
+  ret = drm_->GetCrtcProperty(*this, "OUT_FENCE_PTR", &out_fence_ptr_property_);
+  if (ret) {
+    ALOGE("Failed to get OUT_FENCE_PTR property");
+    return ret;
+  }
   return 0;
 }
 
@@ -81,4 +87,8 @@
 const DrmProperty &DrmCrtc::mode_property() const {
   return mode_property_;
 }
+
+const DrmProperty &DrmCrtc::out_fence_ptr_property() const {
+  return out_fence_ptr_property_;
+}
 }