Enable CAR migration on Exynos 5250 and 5420

Despite calling romstage memory CAR in this case, the variables actually
do live in SRAM on the Exynos CPUs. However, in order to share as much
generic code as possible, we're using the same infrastructure here.

Change-Id: I85173c37099a25f3e55980e88120401826cdf29c
Signed-off-by: Stefan Reinauer <reinauer@google.com>
Reviewed-on: https://gerrit.chromium.org/gerrit/62188
Reviewed-by: David Hendricks <dhendrix@chromium.org>
Commit-Queue: Stefan Reinauer <reinauer@chromium.org>
Tested-by: Stefan Reinauer <reinauer@chromium.org>
Reviewed-on: http://review.coreboot.org/4394
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>

src/arch/armv7/romstage.ld

@@ -52,10 +52,28 @@ SECTIONS
 		*(.rodata);
 		*(.machine_param);
 		*(.data);
-		. = ALIGN(8);
+		. = ALIGN(16);
+		_car_migrate_start = .;
+		*(.car.migrate);
+		_car_migrate_end = .;
+		. = ALIGN(16);
 		_erom = .;
 	}
 
+	.car.data . (NOLOAD) : {
+		_car_data_start = .;
+		*(.car.global_data);
+		/* The cbmem_console section comes last to take advantage of
+		 * a zero-sized array to hold the memconsole contents that
+		 * grows to a bound of CONFIG_CONSOLE_CAR_BUFFER_SIZE. However,
+		 * collisions within the cache-as-ram region cannot be
+		 * statically checked because the cache-as-ram region usage is
+		 * cpu/chipset dependent. */
+		*(.car.cbmem_console);
+		_car_data_end = .;
+	}
+
+
 	__image_copy_end = .;
 
 	/* bss does not contain data, it is just a space that should be zero