arm64: dts: imx8mm-beacon: add more pinctrl states for usdhc1

The WiFi chip is capable of communication at SDR104 speeds.
Enable 100Mhz and 200MHz pinmux to support this.

Signed-off-by: Adam Ford <aford173@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>