USB: usbip: Remove an unnecessary goto

When udc_dev = NULL, it is not necessary to goto out to return, just
return NULL directly. And the out goto label can be removed.

Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/20230805045631.1858638-1-ruanjinjie@huawei.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>