net: Provide MemReentrancyGuard * to qemu_new_nic()

Recently MemReentrancyGuard was added to DeviceState to record that the
device is engaging in I/O. The network device backend needs to update it
when delivering a packet to a device.

In preparation for such a change, add MemReentrancyGuard * as a
parameter of qemu_new_nic().

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Alexander Bulekov <alxndr@bu.edu>
Signed-off-by: Jason Wang <jasowang@redhat.com>

net/net.c

@@ -319,6 +319,7 @@ NICState *qemu_new_nic(NetClientInfo *info,
                        NICConf *conf,
                        const char *model,
                        const char *name,
+                       MemReentrancyGuard *reentrancy_guard,
                        void *opaque)
 {
     NetClientState **peers = conf->peers.ncs;