[AX.25]: Mark all kmalloc users __must_check

The recent fix 0506d4068bad834aab1141b5dc5e748eb175c6b3 made obvious that
error values were not being propagated through the AX.25 stack.  To help
with that this patch marks all kmalloc users in the AX.25, NETROM and
ROSE stacks as __must_check.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/rose.h b/include/net/rose.h
index 012b09e..0143796 100644
--- a/include/net/rose.h
+++ b/include/net/rose.h
@@ -193,8 +193,8 @@
 extern struct file_operations rose_nodes_fops;
 extern struct file_operations rose_routes_fops;
 
-extern int  rose_add_loopback_neigh(void);
-extern int  rose_add_loopback_node(rose_address *);
+extern int __must_check rose_add_loopback_neigh(void);
+extern int __must_check rose_add_loopback_node(rose_address *);
 extern void rose_del_loopback_node(rose_address *);
 extern void rose_rt_device_down(struct net_device *);
 extern void rose_link_device_down(struct net_device *);