arm: dts: Add nodes for flexcan devices present on LS1021A-Rev2 SoC

This patch adds the device nodes for flexcan controller(s) present on
LS1021A-Rev2 SoC.

Signed-off-by: Pankaj Bansal <pankaj.bansal@nxp.com>
Signed-off-by: Bhupesh Sharma <bhupesh.sharma@freescale.com>
Signed-off-by: Sakar Arora <Sakar.Arora@freescale.com>
Reviewed-by: Zhengxiong Jin <Jason.Jin@freescale.com>
Reviewed-by: Poonam Aggrwal <poonam.aggrwal@nxp.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>