net: Use g_strdup_printf instead of snprintf.

assign_name() in net/net.c is using snprintf + g_strdup to get the same
result as g_strdup_printf.

Signed-off-by: Hani Benhabiles <kroosec@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
diff --git a/net/net.c b/net/net.c
index f8db85f..2c3af20 100644
--- a/net/net.c
+++ b/net/net.c
@@ -164,7 +164,6 @@
 static char *assign_name(NetClientState *nc1, const char *model)
 {
     NetClientState *nc;
-    char buf[256];
     int id = 0;
 
     QTAILQ_FOREACH(nc, &net_clients, next) {
@@ -176,9 +175,7 @@
         }
     }
 
-    snprintf(buf, sizeof(buf), "%s.%d", model, id);
-
-    return g_strdup(buf);
+    return g_strdup_printf("%s.%d", model, id);
 }
 
 static void qemu_net_client_destructor(NetClientState *nc)