Add support for all the six CAN controllers of sama7g5.The internal SRAM of 128KB
is split among the CAN controllers for the message RAM elements leaving a small
portion reserved for power management. The SRAM split up is as below.

Lower 64K:
        PM       13K
        can-0    17K
        can-1    17K
        can-2    17K

Higher 64K:

        can-3    17K
        can-4    17K
        can-5    17K
Signed-off-by: Hari Prasath <Hari.PrasathGE@microchip.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20220222113924.25799-2-Hari.PrasathGE@microchip.com