x86: fsp: Allow remembering the location of FSP-S

FSP-S is used by the notify call after it has been used for silicon init.
To avoid having to load it again, add a field to store the location.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

arch/x86/include/asm/global_data.h

@@ -120,6 +120,9 @@ struct arch_global_data {
 	int prev_sleep_state;		/* Previous sleep state ACPI_S0/1../5 */
 	ulong backup_mem;		/* Backup memory address for S3 */
 #endif
+#ifdef CONFIG_FSP_VERSION2
+	struct fsp_header *fsp_s_hdr;	/* Pointer to FSP-S header */
+#endif
 };
 
 #endif