dt-binding: can: m_can: fix indention of table in bosch,mram-cfg description

This patch fixes the indention of the table in the description of the
bosch,mram-cfg property.

Link: https://lore.kernel.org/all/20220217101111.2291151-1-mkl@pengutronix.deReviewed-by: Chandrasekar Ramakrishnan <rcsekar@samsung.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>