include: add linked list implementation from kernel

Rename hlist.h to list.h while adding it to be aligned with kernel

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
diff --git a/ip/ipnetns.c b/ip/ipnetns.c
index 71fbfce..b3ee23c 100644
--- a/ip/ipnetns.c
+++ b/ip/ipnetns.c
@@ -18,7 +18,7 @@
 #include <linux/net_namespace.h>
 
 #include "utils.h"
-#include "hlist.h"
+#include "list.h"
 #include "ip_common.h"
 #include "namespace.h"