- creates proper ifc.h and dhcp.h headers for libnetutils
- adds ifc_set_hwaddr
- adds hwaddr command to netcfg
- code reuse: dhcp_configure calls ifc_configure; inet_ntoa is used for printing
- consistency: use net.XXX.dnsX properties in favor of dhcp.XXX.dnsX properties
  (see related change to WifiStateTracker)
- updated system/core/nexus to use new headers, although not sure if
anybody still uses nexus

Change-Id: Idd70c0ac6e89b38e86816578c33eff805d30cac4
diff --git a/nexus/DhcpClient.cpp b/nexus/DhcpClient.cpp
index a5654d2..713059d 100644
--- a/nexus/DhcpClient.cpp
+++ b/nexus/DhcpClient.cpp
@@ -27,35 +27,15 @@
 
 #include <sysutils/ServiceManager.h>
 
+#include <netutils/ifc.h>
+#include <netutils/dhcp.h>
+
 #include "DhcpClient.h"
 #include "DhcpState.h"
 #include "DhcpListener.h"
 #include "IDhcpEventHandlers.h"
 #include "Controller.h"
 
-extern "C" {
-int ifc_disable(const char *ifname);
-int ifc_add_host_route(const char *ifname, uint32_t addr);
-int ifc_remove_host_routes(const char *ifname);
-int ifc_set_default_route(const char *ifname, uint32_t gateway);
-int ifc_get_default_route(const char *ifname);
-int ifc_remove_default_route(const char *ifname);
-int ifc_reset_connections(const char *ifname);
-int ifc_configure(const char *ifname, in_addr_t ipaddr, in_addr_t netmask, in_addr_t gateway, in_addr_t dns1, in_addr_t dns2);
-
-int dhcp_do_request(const char *ifname,
-                    in_addr_t *ipaddr,
-                    in_addr_t *gateway,
-                    in_addr_t *mask,
-                    in_addr_t *dns1,
-                    in_addr_t *dns2,
-                    in_addr_t *server,
-                    uint32_t  *lease);
-int dhcp_stop(const char *ifname);
-int dhcp_release_lease(const char *ifname);
-char *dhcp_get_errmsg();
-}
-
 DhcpClient::DhcpClient(IDhcpEventHandlers *handlers) :
             mState(DhcpState::INIT), mHandlers(handlers) {
     mServiceManager = new ServiceManager();