USB: usbip: Remove an unnecessary NULL value

The NULL initialization of the pointers assigned by kzalloc() first is
not necessary, because if the kzalloc() failed, the pointers will be
assigned NULL, otherwise it works as usual. so remove it.
Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
Link: https://lore.kernel.org/r/20230804093253.91647-6-ruanjinjie@huawei.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/usbip/vudc_dev.c

@@ -489,7 +489,7 @@ static void vudc_device_unusable(struct usbip_device *ud)
 
 struct vudc_device *alloc_vudc_device(int devid)
 {
-	struct vudc_device *udc_dev = NULL;
+	struct vudc_device *udc_dev;
 
 	udc_dev = kzalloc(sizeof(*udc_dev), GFP_KERNEL);
 	if (!udc_dev)