Update Workflow.h

Author: Barenboim

src/factory/Workflow.h

@@ -262,7 +262,7 @@ class ParallelWork : public ParallelTask
 	SeriesWork *end() { return this->all_series + this->subtasks_nr;}
 
 	const SeriesWork *begin() const { return this->series_at(0);}
-	ccons 	SeriesWork *end() const { return this->all_series + this->subtasks_nr;}
+	const SeriesWork *end() const { return this->all_series + this->subtasks_nr;}
 
 public:
 	void set_callback(parallel_callback_t callback)