can: rcar_canfd: rcar_canfd_handle_channel_tx(): fix redundant assignment

Fix redundant assignment of 'priv' to itself in
rcar_canfd_handle_channel_tx().

Fixes: 76e9353a ("can: rcar_canfd: Add support for RZ/G2L family")
Link: https://lore.kernel.org/r/20210820161449.18169-1-prabhakar.mahadev-lad.rj@bp.renesas.com


Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>