[dhcp] Request NTP server option

Signed-off-by: Michael Brown <mcb30@ipxe.org>
diff --git a/src/net/udp/dhcp.c b/src/net/udp/dhcp.c
index bd2c4a1..8e2e97f 100644
--- a/src/net/udp/dhcp.c
+++ b/src/net/udp/dhcp.c
@@ -91,9 +91,10 @@
 	DHCP_PARAMETER_REQUEST_LIST,
 	DHCP_OPTION ( DHCP_SUBNET_MASK, DHCP_ROUTERS, DHCP_DNS_SERVERS,
 		      DHCP_LOG_SERVERS, DHCP_HOST_NAME, DHCP_DOMAIN_NAME,
-		      DHCP_ROOT_PATH, DHCP_MTU, DHCP_VENDOR_ENCAP,
-		      DHCP_VENDOR_CLASS_ID, DHCP_TFTP_SERVER_NAME,
-		      DHCP_BOOTFILE_NAME, DHCP_DOMAIN_SEARCH,
+		      DHCP_ROOT_PATH, DHCP_MTU, DHCP_NTP_SERVERS,
+		      DHCP_VENDOR_ENCAP, DHCP_VENDOR_CLASS_ID,
+		      DHCP_TFTP_SERVER_NAME, DHCP_BOOTFILE_NAME,
+		      DHCP_DOMAIN_SEARCH,
 		      128, 129, 130, 131, 132, 133, 134, 135, /* for PXE */
 		      DHCP_EB_ENCAP, DHCP_ISCSI_INITIATOR_IQN ),
 	DHCP_END