phy: tegra: xusb: Clear the driver reference in usb-phy dev

For the dual-role port, it will assign the phy dev to usb-phy dev and
use the port dev driver as the dev driver of usb-phy.

When we try to destroy the port dev, it will destroy its dev driver
as well. But we did not remove the reference from usb-phy dev. This
might cause the use-after-free issue in KASAN.

Fixes: e8f7d2f ("phy: tegra: xusb: Add usb-phy support")
Cc: stable@vger.kernel.org

Signed-off-by: EJ Hsu <ejh@nvidia.com>
Signed-off-by: Haotien Hsu <haotienh@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Link: https://lore.kernel.org/r/20230609062932.3276509-1-haotienh@nvidia.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

Author: EJ Hsu

drivers/phy/tegra/xusb.c

@@ -568,6 +568,7 @@ static void tegra_xusb_port_unregister(struct tegra_xusb_port *port)
 		usb_role_switch_unregister(port->usb_role_sw);
 		cancel_work_sync(&port->usb_phy_work);
 		usb_remove_phy(&port->usb_phy);
+		port->usb_phy.dev->driver = NULL;
 	}
 
 	if (port->ops->remove)