commit 4bfb141b upstream.

usbip_host calls device_attach() without holding dev->parent lock.
Fix it.
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>