can: xilinx_can: Add cantype parameter in xcan_devtype_data struct

To differentiate between different CAN IP's this patch adds
cantype enum variable in the xcan_devtype_data structure

Signed-off-by: Appana Durga Kedareswara rao <appana.durga.rao@xilinx.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>