arm64: dts: imx8qxp: add flexcan in adma

Add FlexCAN decive in adma subsystem.

Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com> # TQMa8XQP
Signed-off-by: Shawn Guo <shawnguo@kernel.org>