Clarify ascend/descend description

Add supllementary explainations for q_ascend and q_descend,
indicating the required memory operations that must be
implemented in these functions.

queue.h

@@ -207,6 +207,7 @@ void q_sort(struct list_head *head, bool descend);
  *
  * No effect if queue is NULL or empty. If there has only one element, do
  * nothing.
+ * Memory allocated to removed nodes must be freed.
  *
  * Reference:
  * https://leetcode.com/problems/remove-nodes-from-linked-list/
@@ -222,6 +223,7 @@ int q_ascend(struct list_head *head);
  *
  * No effect if queue is NULL or empty. If there has only one element, do
  * nothing.
+ * Memory allocated to removed nodes must be freed.
  *
  * Reference:
  * https://leetcode.com/problems/remove-nodes-from-linked-list/

scripts/checksums

@@ -1,2 +1,2 @@
-186d420b53e21c6daf8eabe980a5b90780c53bcd  queue.h
+db6784ff3917888db4d1dceaa0570d99ed40e762  queue.h
 3337dbccc33eceedda78e36cc118d5a374838ec7  list.h