arm64: dts: imx8qxp-mek: support wcpu board's wm8962 codec

The i.MX8QXP WCPU MEK board is a reworked version of the i.MX8QXP MEK
board, which includes some sensor and component changes. One of these
components is the WM8962 codec, which is meant to replace the WM8960
codec present on i.MX8QXP MEK. To avoid having to introduce a devicetree
overlay or another DTS, the WM8962 can be supported by using a virtual
I2C MUX since both of the codecs share the same I2C address.

Signed-off-by: Laurentiu Mihalcea <laurentiu.mihalcea@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>