can: gs_usb: gs_usb_disconnect(): remove not needed usb_kill_anchored_urbs()

can: gs_usb: gs_usb_disconnect(): remove not needed usb_kill_anchored_urbs()

In gs_usb_disconnect(), all channels are destroyed first, then all
anchored RX URBs (parent->rx_submitted) are disposed with
usb_kill_anchored_urbs().

The call to usb_kill_anchored_urbs() is not needed, as
gs_destroy_candev() of the last active channel already disposes the RX
URBS.

Remove not needed call to usb_kill_anchored_urbs() from
gs_usb_disconnect().

Link: https://lore.kernel.org/all/20230718-gs_usb-cleanups-v1-11-c3b9154ec605@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>