dt-bindings: arm: ti: Add bindings for J721s2 SoC

Add binding for J721S2 SoC

Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Kishon Vijay Abraham I <kishon@ti.com>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20211207080904.14324-2-a-govindraju@ti.com