phonet: Fix build warning.

net/phonet/socket.c: In function ‘pn_res_seq_show’:
net/phonet/socket.c:726: warning: format ‘%02X’ expects type ‘unsigned int’, but argument 3 has type ‘long int’

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/phonet/socket.c b/net/phonet/socket.c
index 6bf6e3c..aca8fba 100644
--- a/net/phonet/socket.c
+++ b/net/phonet/socket.c
@@ -723,7 +723,8 @@
 		struct sock *sk = *psk;
 
 		seq_printf(seq, "%02X %5d %lu%n",
-			psk - pnres.sk, sock_i_uid(sk), sock_i_ino(sk), &len);
+			   (int) (psk - pnres.sk), sock_i_uid(sk),
+			   sock_i_ino(sk), &len);
 	}
 	seq_printf(seq, "%*s\n", 63 - len, "");
 	return 0;