preferences: adjusts for Path preference

Change-Id: Icf1d0bccec77320ad4b66f90d2999f7210627629
diff --git a/GreenScreen/videoSubscriber.h b/GreenScreen/videoSubscriber.h
index 4e238d4..c7ffd17 100644
--- a/GreenScreen/videoSubscriber.h
+++ b/GreenScreen/videoSubscriber.h
@@ -64,7 +64,7 @@
 
     void detach();
     void stop();
-    void setBackground(const std::string& dataPath, const std::string& value);
+    void setBackground(const std::string& backgroundPath);
 
 
 private: