Added set_netmask() and set_gateway()

src/include/gpxe/ip.h

 #include <gpxe/in.h>
 
 extern void set_ipaddr ( struct in_addr address );
+extern void set_netmask ( struct in_addr address );
+extern void set_gateway ( struct in_addr address );
 extern void init_tcpip ( void );
 extern void run_tcpip ( void );
 

src/proto/ip.c

 	uip_sethostaddr ( u.uip_address );
 }
 
+/**
+ * Set netmask
+ *
+ */
+void set_netmask ( struct in_addr address ) {
+	union {
+		struct in_addr address;
+		uint16_t uip_address[2];
+	} u;
+
+	u.address = address;
+	uip_setnetmask ( u.uip_address );
+}
+
+/**
+ * Set default gateway
+ *
+ */
+void set_gateway ( struct in_addr address ) {
+	union {
+		struct in_addr address;
+		uint16_t uip_address[2];
+	} u;
+
+	u.address = address;
+	uip_setdraddr ( u.uip_address );
+}
+
 /**
  * Initialise TCP/IP stack
  *