usb_put_dev shouldn't be called when uss720_probe succeeds because of
priv->usbdev. At the same time, priv->usbdev shouldn't be set to NULL
before destroy_priv in uss720_disconnect because usb_put_dev is in
destroy_priv.

Fix this by moving priv->usbdev = NULL after usb_put_dev.

Fixes: dcb4b8ad ("misc/uss720: fix memory leak in uss720_probe")
Cc: stable <stable@kernel.org>
Reviewed-by: NDongliang Mu <mudongliangabcd@gmail.com>
Signed-off-by: NHangyu Hua <hbh25y@gmail.com>
Link: https://lore.kernel.org/r/20220407024001.11761-1-hbh25y@gmail.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>