mediatek: mt7623: fix mmc dtc warnings

mediatek: mt7623: fix mmc dtc warnings

Add missing #address-cells and #size-cells to fix the
following dtc warnings:

mt7623n-bananapi-bpi-r2.dts:346.3-13: Warning (reg_format): /mmc@11230000/card@0:reg: property has invalid length (4 bytes) (#address-cells == 2, #size-cells == 1)
mt7623n-bananapi-bpi-r2.dts:373.3-13: Warning (reg_format): /mmc@11240000/card@0:reg: property has invalid length (4 bytes) (#address-cells == 2, #size-cells == 1)
../dts/mt7623a-unielec-u7623-02.dts:23.3-13: Warning (reg_format): /mmc@11230000/card@0:reg: property has invalid length (4 bytes) (#address-cells == 2, #size-cells == 1)

Signed-off-by: Shiji Yang <[email protected]>