cdc_ncm: do not call usbnet_link_change from cdc_ncm_bind

usbnet_link_change will call schedule_work and should be
avoided if bind is failing. Otherwise we will end up with
scheduled work referring to a netdev which has gone away.

Instead of making the call conditional, we can just defer
it to usbnet_probe, using the driver_info flag made for
this purpose.

Fixes: 8a34b0ae8778 ("usbnet: cdc_ncm: apply usbnet_link_change")
Reported-by: Andrey Konovalov <andreyknvl@gmail.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
static void cdc_ncm_get_ethtool_stats(struct net_device *netdev,
				    struct ethtool_stats __always_unused *stats,
				    u64 *data)
{
	struct usbnet *dev = netdev_priv(netdev);
	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
	int i;
	char *p = NULL;

	for (i = 0; i < ARRAY_SIZE(cdc_ncm_gstrings_stats); i++) {
		p = (char *)ctx + cdc_ncm_gstrings_stats[i].stat_offset;
		data[i] = (cdc_ncm_gstrings_stats[i].sizeof_stat == sizeof(u64)) ? *(u64 *)p : *(u32 *)p;
	}
}

static void cdc_ncm_get_ethtool_stats(struct net_device *netdev,
				    struct ethtool_stats __always_unused *stats,
				    u64 *data)
{
	struct usbnet *dev = netdev_priv(netdev);
	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
	int i;
	char *p = NULL;

	for (i = 0; i < ARRAY_SIZE(cdc_ncm_gstrings_stats); i++) {
		p = (char *)ctx + cdc_ncm_gstrings_stats[i].stat_offset;
		data[i] = (cdc_ncm_gstrings_stats[i].sizeof_stat == sizeof(u64)) ? *(u64 *)p : *(u32 *)p;
	}
}
