Revert "usb: gadget: u_serial: Disable ep before setting port to null to fix the crash caused by port being null"

This reverts commit 1301496.

It is reported to cause crashes on Tegra systems, so revert it for now.

Link: https://lore.kernel.org/r/1037c1ad-9230-4181-b9c3-167dbaa47644@nvidia.com
Reported-by: Jon Hunter <jonathanh@nvidia.com>
Cc: stable <stable@kernel.org>
Cc: Lianqin Hu <hulianqin@vivo.com>
Link: https://lore.kernel.org/r/2025011711-yippee-fever-a737@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: gregkh

drivers/usb/gadget/function/u_serial.c

@@ -1421,10 +1421,6 @@ void gserial_disconnect(struct gserial *gser)
 	/* REVISIT as above: how best to track this? */
 	port->port_line_coding = gser->port_line_coding;
 
-	/* disable endpoints, aborting down any active I/O */
-	usb_ep_disable(gser->out);
-	usb_ep_disable(gser->in);
-
 	port->port_usb = NULL;
 	gser->ioport = NULL;
 	if (port->port.count > 0) {
@@ -1436,6 +1432,10 @@ void gserial_disconnect(struct gserial *gser)
 	spin_unlock(&port->port_lock);
 	spin_unlock_irqrestore(&serial_port_lock, flags);
 
+	/* disable endpoints, aborting down any active I/O */
+	usb_ep_disable(gser->out);
+	usb_ep_disable(gser->in);
+
 	/* finally, free any unused/unusable I/O buffers */
 	spin_lock_irqsave(&port->port_lock, flags);
 	if (port->port.count == 0)