can: etas_es58x: clean-up documentation of struct es58x_fd_tx_conf_msg

The documentation of struct es58x_fd_tx_conf_msg explains in details
the different TDC parameters. However, those description are redundant
with the documentation of struct can_tdc.

Remove most of the description.

Also, fixes a typo in the reference to the datasheet (E701 -> E70).

Link: https://lore.kernel.org/r/20210815033248.98111-8-mailhol.vincent@wanadoo.fr


Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>