drivers: can: add kconfig CAN_MAX_MB

Each CAN instance of S32K344 has different maximum number
of message buffers, depends on payload. Add kconfig that
defines maximum number of message buffers for concurrent
active instances and update driver to compatible
support S32k344.

Signed-off-by: Cong Nguyen Huu <cong.nguyenhuu@nxp.com>