x86: acpi: Resume OS if resume vector is found

In an S3 resume path, U-Boot does everything like a cold boot except
in the last_stage_init() it jumps to the OS resume vector.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Stefan Roese <sr@denx.de>
diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
index d1ad37a..21f59a0 100644
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -37,6 +37,7 @@
 obj-y	+= sections.o
 obj-y += sfi.o
 obj-y	+= string.o
+obj-$(CONFIG_HAVE_ACPI_RESUME) += acpi_s3.o
 ifndef CONFIG_QEMU
 obj-$(CONFIG_GENERATE_ACPI_TABLE) += acpi_table.o
 endif