Do not allow modifying memory table directly

Adding ranges directly into coreboot memory table raised issues
as those methods bypassed the MTRR setup. Such regions are now
added as resources, so declare the functions again as static.

Change-Id: If78613da40eabc5c99c49dbe2d6047cb22a71b69
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/1415
Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Tested-by: build bot (Jenkins)

src/include/boot/tables.h

@@ -4,9 +4,6 @@
 #include <boot/coreboot_tables.h>
 #include <arch/coreboot_tables.h>
 
-void lb_add_memory_range(struct lb_memory *mem,
-	uint32_t type, uint64_t start, uint64_t size);
-
 struct lb_memory *write_tables(void);
 
 #endif /* BOOT_TABLES_H */