Refactor RPC input generation

Change-Id: I4fac9ffc939a7df41a6e3f3332199da0070edb9e
diff --git a/src/libyang_utils.hpp b/src/libyang_utils.hpp
index a33e70b..b5f5e96 100644
--- a/src/libyang_utils.hpp
+++ b/src/libyang_utils.hpp
@@ -11,3 +11,5 @@
 
 leaf_data_ leafValueFromNode(libyang::S_Data_Node_Leaf_List node);
 void lyNodesToTree(DatastoreAccess::Tree& res, const std::vector<std::shared_ptr<libyang::Data_Node>> items, std::optional<std::string> ignoredXPathPrefix = std::nullopt);
+libyang::S_Data_Node treeToRpcInput(libyang::S_Context ctx, const std::string& path, DatastoreAccess::Tree in);
+DatastoreAccess::Tree rpcOutputToTree(const std::string& rpcPath, libyang::S_Data_Node output);