MINOR: task: export run_tasks_from_list

This will help refine debug traces.
diff --git a/include/proto/task.h b/include/proto/task.h
index 68a0a18..84c2f8a 100644
--- a/include/proto/task.h
+++ b/include/proto/task.h
@@ -608,6 +608,7 @@
                                    void *arg);
 
 void work_list_destroy(struct work_list *work, int nbthread);
+int run_tasks_from_list(struct list *list, int max);
 
 /*
  * This does 3 things :
diff --git a/src/task.c b/src/task.c
index 319ae93..2952d2a 100644
--- a/src/task.c
+++ b/src/task.c
@@ -319,7 +319,7 @@
  * the number of entries effectively processed (tasks and tasklets merged).
  * The count of tasks in the list for the current thread is adjusted.
  */
-static int run_tasks_from_list(struct list *list, int max)
+int run_tasks_from_list(struct list *list, int max)
 {
 	struct task *(*process)(struct task *t, void *ctx, unsigned short state);
 	struct task *t;