arm64: dts: renesas: r8a77980: add resets property to CAN-FD node

Add resets property to CAN-FD node to describe it in the reset topology of
on-SoC devices.  This allows to reset the CAN-FD device using the Reset
Controller API.

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>