CBMEM: Implement cbmem_run_init_hooks() stub

Until we completely can unify early_variables, use these to
handle CBMEM update hooks for both romstage and ramstage.

For x86, CAR_MIGRATE serves the purpose of romstage hooks.

Change-Id: I100ebc0e35e1b7091b4f287ca37f539fd7c9fa7a
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/7876
Reviewed-by: Aaron Durbin <adurbin@google.com>
Tested-by: build bot (Jenkins)

src/arch/x86/boot/tables.c

@@ -21,7 +21,6 @@
 
 #include <console/console.h>
 #include <cpu/cpu.h>
-#include <cpu/x86/gdt.h>
 #include <boot/tables.h>
 #include <boot/coreboot_tables.h>
 #include <arch/pirq_routing.h>
@@ -31,13 +30,6 @@
 #include <cbmem.h>
 #include <smbios.h>
 
-
-void cbmem_arch_init(void)
-{
-	/* defined in gdt.c */
-	move_gdt();
-}
-
 void write_tables(void)
 {
 	unsigned long low_table_start, low_table_end;