ACPI: Add missing prototype for non CONFIG_SUSPEND/CONFIG_X86 case

BugLink: https://bugs.launchpad.net/bugs/2120812

[ Upstream commit e1bdbbc98279164d910d2de82a745f090a8b249f ]

acpi_register_lps0_dev() and acpi_unregister_lps0_dev() may be used
in drivers that don't require CONFIG_SUSPEND or compile on !X86.

Add prototypes for those cases.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202502191627.fRgoBwcZ-lkp@intel.com/
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Link: https://patch.msgid.link/20250407183656.1503446-1-superm1@kernel.org
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Noah Wager <noah.wager@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

Author: superm1

include/linux/acpi.h

@@ -1115,13 +1115,13 @@ 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);
-#if defined(CONFIG_SUSPEND) && defined(CONFIG_X86)
 struct acpi_s2idle_dev_ops {
 	struct list_head list_node;
 	void (*prepare)(void);
 	void (*check)(void);
 	void (*restore)(void);
 };
+#if defined(CONFIG_SUSPEND) && defined(CONFIG_X86)
 int acpi_register_lps0_dev(struct acpi_s2idle_dev_ops *arg);
 void acpi_unregister_lps0_dev(struct acpi_s2idle_dev_ops *arg);
 int acpi_get_lps0_constraint(struct acpi_device *adev);
@@ -1130,6 +1130,13 @@ static inline int acpi_get_lps0_constraint(struct device *dev)
 {
 	return ACPI_STATE_UNKNOWN;
 }
+static inline int acpi_register_lps0_dev(struct acpi_s2idle_dev_ops *arg)
+{
+	return -ENODEV;
+}
+static inline void acpi_unregister_lps0_dev(struct acpi_s2idle_dev_ops *arg)
+{
+}
 #endif /* CONFIG_SUSPEND && CONFIG_X86 */
 void arch_reserve_mem_area(acpi_physical_address addr, size_t size);
 #else