vexpress64_fvp: Set DRAM to 4G to match with kernel devicetree

Currently, the kernel devicetree is setting the DRAM size to ~4G.
Signed-off-by: NDiego Sueiro <diego.sueiro@arm.com>

configs/vexpress_aemv8a_semi_defconfig

@@ -2,7 +2,7 @@ CONFIG_ARM=y
 CONFIG_TARGET_VEXPRESS64_BASE_FVP=y
 CONFIG_SYS_TEXT_BASE=0x88000000
 CONFIG_SYS_MALLOC_F_LEN=0x2000
-CONFIG_NR_DRAM_BANKS=1
+CONFIG_NR_DRAM_BANKS=2
 CONFIG_SYS_MEMTEST_START=0x80000000
 CONFIG_SYS_MEMTEST_END=0xff000000
 CONFIG_ENV_SIZE=0x40000

include/configs/vexpress_aemv8a.h

@@ -117,6 +117,9 @@
 #ifdef CONFIG_TARGET_VEXPRESS64_JUNO
 #define PHYS_SDRAM_2			(0x880000000)
 #define PHYS_SDRAM_2_SIZE		0x180000000
+#elif CONFIG_TARGET_VEXPRESS64_BASE_FVP && CONFIG_NR_DRAM_BANKS == 2
+#define PHYS_SDRAM_2			(0x880000000)
+#define PHYS_SDRAM_2_SIZE		0x80000000
 #endif
 
 /* Enable memtest */