ARM: dts: dra7: Add supported MMC/SD modes in MMC dt nodes

On DRA7 family SoCs, MMC1 controller supports SDR104,
SDR50, DDR50, SDR25 and SDR12 UHS modes.

MMC2 controller supports HS200 and DDR modes.

MMC3 controller supports SDR12, SDR25 and SDR50 modes.

MMC4 controller supports SDR12 and SDR25 modes.

Add these supported modes in device-tree file.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>