net-procfs: Use vsnprintf extension %phN

Save a bit of code by using the kernel extension.

$ size net/core/net-procfs.o*
   text	   data	    bss	    dec	    hex	filename
   3701	    120	      0	   3821	    eed	net/core/net-procfs.o.new
   3764	    120	      0	   3884	    f2c	net/core/net-procfs.o.old
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/core/net-procfs.c

@@ -363,15 +363,10 @@ static int dev_mc_seq_show(struct seq_file *seq, void *v)
 
 	netif_addr_lock_bh(dev);
 	netdev_for_each_mc_addr(ha, dev) {
-		int i;
-
-		seq_printf(seq, "%-4d %-15s %-5d %-5d ", dev->ifindex,
-			   dev->name, ha->refcount, ha->global_use);
-
-		for (i = 0; i < dev->addr_len; i++)
-			seq_printf(seq, "%02x", ha->addr[i]);
-
-		seq_putc(seq, '\n');
+		seq_printf(seq, "%-4d %-15s %-5d %-5d %*phN\n",
+			   dev->ifindex, dev->name,
+			   ha->refcount, ha->global_use,
+			   (int)dev->addr_len, ha->addr);
 	}
 	netif_addr_unlock_bh(dev);
 	return 0;