Support for UDP unicast network backend

Signed-off-by: Benjamin MARSILI <mlspirat42@gmail.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/net.c b/net.c
index f7bebf8..2b0f766 100644
--- a/net.c
+++ b/net.c
@@ -1000,7 +1000,11 @@
             }, {
                 .name = "localaddr",
                 .type = QEMU_OPT_STRING,
-                .help = "source address for multicast packets",
+                .help = "source address and port for multicast and udp packets",
+            }, {
+                .name = "udp",
+                .type = QEMU_OPT_STRING,
+                .help = "UDP unicast address and port number",
             },
             { /* end of list */ }
         },