Revert "ACPI battery: fix async boot oops"

This reverts commit 5d38258e, since the
underlying problem got fixed properly in the previous commit ("async:
Fix module loading async-work regression").

Cc: Arkadiusz Miskiewicz <a.miskiewicz@gmail.com>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
Cc: Len Brown <len.brown@intel.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

drivers/acpi/battery.c

@@ -903,7 +903,7 @@ static struct acpi_driver acpi_battery_driver = {
 		},
 };
 
-static void acpi_battery_init_async(void *unused, async_cookie_t cookie)
+static void __init acpi_battery_init_async(void *unused, async_cookie_t cookie)
 {
 	if (acpi_disabled)
 		return;