x86: Move coreboot sysinfo parsing into generic x86 code

It is useful to be able to parse coreboot tables on any x86 build which is
booted from coreboot. Add a new Kconfig option to enable this feature and
move the code so it can be used on any board, if enabled.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
index 1bcbb49..65d9b3b 100644
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -15,6 +15,7 @@
 obj-$(CONFIG_CMD_BOOTM) += bootm.o
 endif
 obj-y	+= cmd_boot.o
+obj-$(CONFIG_$(SPL_)COREBOOT_SYSINFO)	+= coreboot/
 obj-$(CONFIG_SEABIOS) += coreboot_table.o
 obj-y	+= early_cmos.o
 obj-y	+= e820.o