Fix some more print() format errors.

Signed-off-by: Wolfgang Denk <wd@denx.de>
diff --git a/net/net.c b/net/net.c
index f55c7fa..2a26bc0 100644
--- a/net/net.c
+++ b/net/net.c
@@ -1520,7 +1520,8 @@
 				xsum = (xsum & 0x0000ffff) + ((xsum >> 16) & 0x0000ffff);
 			}
 			if ((xsum != 0x00000000) && (xsum != 0x0000ffff)) {
-				printf(" UDP wrong checksum %08x %08x\n", xsum, ntohs(ip->udp_xsum));
+				printf(" UDP wrong checksum %08lx %08x\n",
+					xsum, ntohs(ip->udp_xsum));
 				return;
 			}
 		}