usb: replace handle_destroy with unrealize

Curiously, unrealize() is not being used, but it seems more
appropriate than handle_destroy() together with realize(). It is more
ubiquitous destroy name in qemu code base and may throw errors.

Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20170221141451.28305-25-marcandre.lureau@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
diff --git a/hw/usb/dev-network.c b/hw/usb/dev-network.c
index c0f1193..85fc81b 100644
--- a/hw/usb/dev-network.c
+++ b/hw/usb/dev-network.c
@@ -1324,7 +1324,7 @@
     s->nic = NULL;
 }
 
-static void usb_net_handle_destroy(USBDevice *dev)
+static void usb_net_unrealize(USBDevice *dev, Error **errp)
 {
     USBNetState *s = (USBNetState *) dev;
 
@@ -1428,7 +1428,7 @@
     uc->handle_reset   = usb_net_handle_reset;
     uc->handle_control = usb_net_handle_control;
     uc->handle_data    = usb_net_handle_data;
-    uc->handle_destroy = usb_net_handle_destroy;
+    uc->unrealize      = usb_net_unrealize;
     set_bit(DEVICE_CATEGORY_NETWORK, dc->categories);
     dc->fw_name = "network";
     dc->vmsd = &vmstate_usb_net;