Remove dev-bluetooth.c dependency from vl.c

Use usb_legacy_register handling to create bt-dongle device and remove code
dependency from vl.c so CONFIG_USB_BLUETOOTH can be disabled.

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
diff --git a/vl.c b/vl.c
index faefd9f..4e709d5 100644
--- a/vl.c
+++ b/vl.c
@@ -1457,8 +1457,10 @@
 
 static int usb_device_add(const char *devname)
 {
-    const char *p;
     USBDevice *dev = NULL;
+#ifndef CONFIG_LINUX
+    const char *p;
+#endif
 
     if (!usb_enabled(false)) {
         return -1;
@@ -1474,15 +1476,8 @@
     /* only the linux version is qdev-ified, usb-bsd still needs this */
     if (strstart(devname, "host:", &p)) {
         dev = usb_host_device_open(usb_bus_find(-1), p);
-    } else
-#endif
-    if (!strcmp(devname, "bt") || strstart(devname, "bt:", &p)) {
-        dev = usb_bt_init(usb_bus_find(-1),
-                          devname[2] ? hci_init(p)
-                                     : bt_new_hci(qemu_find_bt_vlan(0)));
-    } else {
-        return -1;
     }
+#endif
     if (!dev)
         return -1;