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 <kostap@marvell.com>
Reviewed-on: http://vgitil04.il.marvell.com:8080/61279

Reviewed-by: Stefan Chulski <stefanc@marvell.com>
Tested-by: iSoC Platform CI <ykjenk@marvell.com>

docs/marvell/build.txt

@@ -78,9 +78,11 @@ Build Instructions
 		Supported Options:
 			- DDR3 1CS (0): DB-88F3720-DDR3-Modular (512MB); EspressoBIN (512MB)
 			- DDR4 1CS (1): DB-88F3720-DDR4-Modular (512MB)
-			- DDR3 2CS (2): EspressoBIN (1GB)
+			- DDR3 2CS (2): EspressoBIN V3-V5 (1GB)
 			- DDR4 2CS (3): DB-88F3720-DDR4-Modular (4GB)
 			- DDR3 1CS (4): DB-88F3720-DDR3-Modular (1GB)
+			- DDR4 1CS (5): EspressoBin V7 (1GB)
+			- DDR4 2CS (6): EspressoBin V7 (2GB)
 			- CUSTOMER (CUST): Customer board, DDR3 1CS 512MB
 
 	- CLOCKSPRESET: For Armada37x0 only, the clock tree configuration preset including CPU and DDR frequency,