x86: Store and display previous sleep state

Add one member in the global data to store previous sleep state,
and display the state during boot in print_cpuinfo().

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/fsp/fsp_common.c b/arch/x86/lib/fsp/fsp_common.c
index cc42cad..f2d50ac 100644
--- a/arch/x86/lib/fsp/fsp_common.c
+++ b/arch/x86/lib/fsp/fsp_common.c
@@ -82,6 +82,7 @@
 	int boot_mode = BOOT_FULL_CONFIG;
 #ifdef CONFIG_HAVE_ACPI_RESUME
 	int prev_sleep_state = chipset_prev_sleep_state();
+	gd->arch.prev_sleep_state = prev_sleep_state;
 #endif
 
 	if (!gd->arch.hob_list) {