iplink_can: add CAN XL transceiver mode setting (TMS) support

iplink_can: add CAN XL transceiver mode setting (TMS) support

This is the iproute2 counterpart of Linux kernel's commit 233134af2086
("can: netlink: add CAN_CTRLMODE_XL_TMS flag").

The Transceiver Mode Switching (TMS) indicates whether the CAN XL
controller shall use the PWM or NRZ encoding during the data phase.

The term "transceiver mode switching" is used in both ISO 11898-1 and CiA
612-2 (although only the latter one uses the abbreviation TMS). We adopt
the same naming convention here for consistency.

Add the "tms" option to iplink_can which controls the CAN_CTRLMODE_XL_TMS
flag of the CAN netlink interface.

Signed-off-by: Vincent Mailhol <mailhol@kernel.org>