Static CBMEM / CAR: Flag boards with BROKEN_CAR_MIGRATE

Use of CAR_GLOBAL is not safe after CAR is torn down, unless the
board properly implements EARLY_CBMEM_INIT.

Flag vulnerable boards that only do cbmem_recovery() in romstage on S3
resume and implementation with Intel FSP that invalidates cache before
we have a chance to copy the contents.

Change-Id: Iecd10dee9b73ab3f1f66826950fa0945675ff39f
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/5419
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@google.com>

src/mainboard/iwave/iWRainbowG6/Kconfig

@@ -14,6 +14,7 @@ config BOARD_SPECIFIC_OPTIONS # dummy
 	select HAVE_ACPI_TABLES
 	select BOARD_ROMSIZE_KB_1024
 	select GFXUMA
+	select BROKEN_CAR_MIGRATE
 
 config MAINBOARD_DIR
 	string