arch/x86: Drop some __SMM__ guards

Change-Id: I64063bbae5b44f1f24566609a7f770c6d5f69fac
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/36637
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

src/southbridge/intel/ibexpeak/nvs.h

@@ -153,8 +153,7 @@ typedef struct global_nvs_t {
 } __packed global_nvs_t;
 check_member(global_nvs_t, chromeos, GNVS_CHROMEOS_ACPI_OFFSET);
 
-#ifdef __SMM__
 /* Used in SMM to find the ACPI GNVS address */
 global_nvs_t *smm_get_gnvs(void);
-#endif
+
 void acpi_create_gnvs(global_nvs_t *gnvs);