arm64: dts: ti: k3-j7200-som-p0: Add nodes for OSPI0

TI J7200 has the Cadence OSPI controller for interfacing with OSPI
flashes. Add its node to allow using SPI flashes.

Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20210305153926.3479-4-p.yadav@ti.com