doc: marvell: Update build manual with new memory layouts
doc: marvell: Update build manual with new memory layouts

Add description for memory layouts used by EspressoBin v7 (DDR4)

Change-Id: I199d8b52580b26e560f14b503a6e99d32de4f284
Signed-off-by: Konstantin Porotchkin <4c7b7a89ae2c24f675bc0a94dfa7c7466687a3de@marvell.com>
Reviewed-on: http://vgitil04.il.marvell.com:8080/61279
Reviewed-by: Stefan Chulski <be4d9df2337c290f4fcfd1aa8d8aece66a7603c9@marvell.com>
Tested-by: iSoC Platform CI <9ad070efb381c7bf342ccbb378952be7ae2ada85@marvell.com>

achingupta/arm-trusted-firmware,achingupta/arm-trusted-firmware