arm64: dts: imx8dxl: add usb1 and usb2 support

There are two chipidea usb controller in 8dxl.
Add usb node at common connect subsystem.
Enable two usb at imx8dxl_evk boards dts.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>