doc: board: ti: Add SPDX License to svg images

Add Licensing to svg images to clarify the terms.

Signed-off-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>

doc: board: ti: j721e: Update with boot flow diagram

Update the bootflow svg diagram instead of the ascii version

Reviewed-by: Neha Malcom Francis <n-francis@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>

doc: board: ti: j721e: Update with boot flow diagram

Update the bootflow svg diagram instead of the ascii version

Reviewed-by: Neha Malcom Francis <n-francis@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>