armv8: mmu: Add support of non-identical mapping

Introduce virtual and physical addresses in the mapping table. This change
have no impact on existing boards because they all use idential mapping.

Signed-off-by: York Sun <york.sun@nxp.com>
diff --git a/board/raspberrypi/rpi/rpi.c b/board/raspberrypi/rpi/rpi.c
index c45ddb1..fbfbf6c 100644
--- a/board/raspberrypi/rpi/rpi.c
+++ b/board/raspberrypi/rpi/rpi.c
@@ -234,12 +234,14 @@
 #ifdef CONFIG_ARM64
 static struct mm_region bcm2837_mem_map[] = {
 	{
-		.base = 0x00000000UL,
+		.virt = 0x00000000UL,
+		.phys = 0x00000000UL,
 		.size = 0x3f000000UL,
 		.attrs = PTE_BLOCK_MEMTYPE(MT_NORMAL) |
 			 PTE_BLOCK_INNER_SHARE
 	}, {
-		.base = 0x3f000000UL,
+		.virt = 0x3f000000UL,
+		.phys = 0x3f000000UL,
 		.size = 0x01000000UL,
 		.attrs = PTE_BLOCK_MEMTYPE(MT_DEVICE_NGNRNE) |
 			 PTE_BLOCK_NON_SHARE |