ACPI: Adjust #ifdef for *_lps0_dev use

The `#ifdef` for acpi_register_lps0_dev() currently is guarded against
`CONFIG_X86`, but actually the functions contained in the block are
specifically sleep related functions.
Adjust the guard to also check for `CONFIG_SUSPEND`.

Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

include/linux/acpi.h

@@ -1100,7 +1100,7 @@ void acpi_os_set_prepare_extended_sleep(int (*func)(u8 sleep_state,
 
 acpi_status acpi_os_prepare_extended_sleep(u8 sleep_state,
 					   u32 val_a, u32 val_b);
-#ifdef CONFIG_X86
+#if defined(CONFIG_SUSPEND) && defined(CONFIG_X86)
 struct acpi_s2idle_dev_ops {
 	struct list_head list_node;
 	void (*prepare)(void);
@@ -1109,7 +1109,7 @@ struct acpi_s2idle_dev_ops {
 };
 int acpi_register_lps0_dev(struct acpi_s2idle_dev_ops *arg);
 void acpi_unregister_lps0_dev(struct acpi_s2idle_dev_ops *arg);
-#endif /* CONFIG_X86 */
+#endif /* CONFIG_SUSPEND && CONFIG_X86 */
 #ifndef CONFIG_IA64
 void arch_reserve_mem_area(acpi_physical_address addr, size_t size);
 #else