arm64: dts: imx8: move samsung,burst-clock-frequency to imx8mn and imx8mm mba8mx board file

Move 'samsung,burst-clock-frequency' and 'samsung,esc-clock-frequency'
properties to i.MX8MN and i.MX8MM mba8mx board file. These properties are
not applicable to i.MX8MQ MIPI DSI, which uses the compatible string
'fsl,imx8mq-nwl-dsi'. The properties are only valid for i.MX8MM and i.MX8MN
devices with the compatible string 'fsl,imx8mm-mipi-dsim', as described in
samsung,mipi-dsim.yaml.

Fix warning:
arch/arm64/boot/dts/freescale/imx8mq-tqma8mq-mba8mx-lvds-tm070jvhg33.dtb: dsi@30a00000:
    Unevaluated properties are not allowed ('ports', 'samsung,burst-clock-frequency', 'samsung,esc-clock-frequency' were unexpected)
        from schema $id: http://devicetree.org/schemas/display/bridge/nwl-dsi.yaml#



Signed-off-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>