soc: ti: k3-socinfo: Add entry for J784S4 SoC

Add support for J784S4 SoC Identification.

Signed-off-by: Hari Nagalla <hnagalla@ti.com>
Signed-off-by: Apurva Nandan <a-nandan@ti.com>
Reviewed-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Roger Quadros <rogerq@kernel.org>
Tested-by: Marcel Ziswiler <marcel.ziswiler@toradex.com> # AM69-SK