RZ/G2L SoM has both 64 GB eMMC and microSD connected to SDHI0.

Both these interfaces are mutually exclusive and the SD0 device
selection is based on the XOR between GPIO_SD0_DEV_SEL and SW1[2]
switch position.

This patch sets GPIO_SD0_DEV_SEL to high in DT. Use the below switch
setting logic for device selection between eMMC and microSD slot
connected to SDHI0.

Set SW1[2] to position 2/OFF for selecting eMMC
Set SW1[2] to position 3/ON for selecting microSD

This patch enables eMMC on RZ/G2L SMARC platform by default.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/r/20211010142520.21976-2-biju.das.jz@bp.renesas.comSigned-off-by: Geert Uytterhoeven <geert+renesas@glider.be>