mainboard/facebook/watson: Reclaim unused flash space

Currently FMAP does not allocate all the usable space. This change
addresses that by removing unused section and expanding CBFS section.

TEST=tested on actual watson HW

Change-Id: I5f407c11031822d58f11f1a4684845d57653b190
Signed-off-by: Andrey Petrov <anpetrov@fb.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/37474
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Werner Zeh <werner.zeh@siemens.com>
Reviewed-by: Frans Hendriks <fhendriks@eltan.com>

src/mainboard/facebook/watson/board.fmd

@@ -20,7 +20,6 @@ FLASH@0xff000000 0x1000000 {
 		# This only exists to satisfy tools that specifically
 		# look for RO_VPD.
 		RO_VPD@0x30000 0x1000
-		UNUSED_4@0x31000 0x1cf000
-		COREBOOT(CBFS)@0x200000 0x800000
+		COREBOOT(CBFS)@0x31000 0x9cf000
 	}
 }