arm64: dts: ti: k3-am69-sk: Add eMMC mmc0 support

Add support for eMMC card connected to main sdhci0 instance.

Signed-off-by: Dasnavis Sabiya <sabiya.d@ti.com>
Reviewed-by: Nishanth Menon <nm@ti.com>
Link: https://lore.kernel.org/r/20230605174551.160262-1-sabiya.d@ti.com


Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>