can: flexcan: move driver into separate sub directory

This patch moves the flexcan driver into a separate directory, a later
patch will add more files.

Link: https://lore.kernel.org/all/20220107193105.1699523-2-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
3 files changed