can: mcp251xfd: mcp251xfd_stop(): add missing hrtimer_cancel()

can: mcp251xfd: mcp251xfd_stop(): add missing hrtimer_cancel()

In commit 2cebcedc45bf ("can: mcp251xfd: add TX IRQ coalescing
support") software based TX coalescing was added to the driver. The
key idea is to keep the TX complete IRQ disabled for some time after
processing it and re-enable later by a hrtimer. When bringing the
interface down, this timer has to be stopped.

Add the missing hrtimer_cancel() of the tx_irq_time hrtimer to
mcp251xfd_stop().

Link: https://lore.kernel.org/all/20220620143942.891811-1-mkl@pengutronix.de
Fixes: 2cebcedc45bf ("can: mcp251xfd: add TX IRQ coalescing support")
Cc: stable@vger.kernel.org # v5.18
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>