Revert "can: dev: Move device back to init netns on owning netns delete"

This reverts commit 00e17e57a3 which is
commit 3a5ca857079ea022e0b1b17fc154f7ad7dbc150f upstream.

It breaks the networking api and we do not care about CAN devices in
Android systems at this point in time.

Bug: 161946584
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I5d5de8fccb077249478b7d1e136f91d6be0b20cd

drivers/net/can/dev.c

@@ -1235,7 +1235,6 @@ static void can_dellink(struct net_device *dev, struct list_head *head)
 
 static struct rtnl_link_ops can_link_ops __read_mostly = {
 	.kind		= "can",
-	.netns_refund	= true,
 	.maxtype	= IFLA_CAN_MAX,
 	.policy		= can_policy,
 	.setup		= can_setup,

include/net/rtnetlink.h

@@ -33,7 +33,6 @@ static inline int rtnl_msg_family(const struct nlmsghdr *nlh)
  *
  *	@list: Used internally
  *	@kind: Identifier
- *	@netns_refund: Physical device, move to init_net on netns exit
  *	@maxtype: Highest device specific netlink attribute number
  *	@policy: Netlink policy for device specific attribute validation
  *	@validate: Optional validation function for netlink/changelink parameters
@@ -65,7 +64,6 @@ struct rtnl_link_ops {
 	size_t			priv_size;
 	void			(*setup)(struct net_device *dev);
 
-	bool			netns_refund;
 	unsigned int		maxtype;
 	const struct nla_policy	*policy;
 	int			(*validate)(struct nlattr *tb[],

net/core/dev.c

@@ -9725,7 +9725,7 @@ static void __net_exit default_device_exit(struct net *net)
 			continue;
 
 		/* Leave virtual devices for the generic cleanup */
-		if (dev->rtnl_link_ops && !dev->rtnl_link_ops->netns_refund)
+		if (dev->rtnl_link_ops)
 			continue;
 
 		/* Push remaining network devices to init_net */