[NETLINK]: Use nlmsg_trim() where appropriate

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/decnet/dn_table.c b/net/decnet/dn_table.c
index 544c455..d6615c9 100644
--- a/net/decnet/dn_table.c
+++ b/net/decnet/dn_table.c
@@ -28,6 +28,7 @@
 #include <asm/uaccess.h>
 #include <linux/route.h> /* RTF_xxx */
 #include <net/neighbour.h>
+#include <net/netlink.h>
 #include <net/dst.h>
 #include <net/flow.h>
 #include <net/fib_rules.h>
@@ -349,7 +350,7 @@
 
 nlmsg_failure:
 rtattr_failure:
-	skb_trim(skb, b - skb->data);
+	nlmsg_trim(skb, b);
 	return -EMSGSIZE;
 }