staging: lustre: obdclass: Use list_for_each_entry_safe

Doubly linked lists which are  iterated  using list_empty
and list_entry macros have been replaced with list_for_each_entry_safe
macro.
This makes the iteration simpler and more readable.

This patch replaces the while loop containing list_empty and list_entry
with list_for_each_entry_safe.

This was done with Coccinelle.

@@
expression E1;
identifier I1, I2;
type T;
iterator name list_for_each_entry_safe;
@@

T *I1;
+ T *tmp;
...
- while (list_empty(&E1) == 0)
+ list_for_each_entry_safe (I1, tmp, &E1, I2)
{
...when != T *I1;
- I1 = list_entry(E1.next, T, I2);
...
}

Signed-off-by: Bhaktipriya Shridhar <bhaktipriya96@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/obdclass/lustre_peer.c

@@ -150,6 +150,7 @@ int class_del_uuid(const char *uuid)
 {
 	LIST_HEAD(deathrow);
 	struct uuid_nid_data *data;
+	struct uuid_nid_data *temp;
 
 	spin_lock(&g_uuid_lock);
 	if (uuid) {
@@ -171,9 +172,7 @@ int class_del_uuid(const char *uuid)
 		return -EINVAL;
 	}
 
-	while (!list_empty(&deathrow)) {
-		data = list_entry(deathrow.next, struct uuid_nid_data,
-				  un_list);
+	list_for_each_entry_safe(data, temp, &deathrow, un_list) {
 		list_del(&data->un_list);
 
 		CDEBUG(D_INFO, "del uuid %s %s/%d\n",