x86: Move acpi_s3.h to a common location

At present this hedaer is only available on x86. To allow sandbox to use
it for testing, move it to a common location.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/arch/x86/lib/acpi_s3.c b/arch/x86/lib/acpi_s3.c
index 0391718..197636c 100644
--- a/arch/x86/lib/acpi_s3.c
+++ b/arch/x86/lib/acpi_s3.c
@@ -4,8 +4,8 @@
  */
 
 #include <common.h>
+#include <acpi_s3.h>
 #include <asm/acpi.h>
-#include <asm/acpi_s3.h>
 #include <asm/acpi_table.h>
 #include <asm/post.h>
 #include <linux/linkage.h>