Per gpio-sbu-mux.yaml, the compatible entry is incomplete.

The imx8qxp-mek board uses a CBDTU02043, so complete the gpio-sbu-mux
compatible accordingly.

This fixes the following schema warning:

imx8qxp-mek.dtb: gpio-sbu-mux: compatible:0: 'gpio-sbu-mux' is not one of ['onnn,fsusb43l10x', 'pericom,pi3usb102']
	from schema $id: http://devicetree.org/schemas/usb/gpio-sbu-mux.yaml#Signed-off-by: Fabio Estevam <festevam@denx.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>