ACPICA: Linux headers: Remove ACPI_PREEMPTION_POINT() due to no usages.

This patch deletes deprecated ACPI_PREEMPTION_POINT(), there is no user
for it in Linux kernel now.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

include/acpi/platform/aclinux.h

@@ -228,20 +228,6 @@ static inline acpi_thread_id acpi_os_get_thread_id(void)
 
 #define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_get_thread_id
 
-#ifndef CONFIG_PREEMPT
-
-/*
- * Used within ACPICA to show where it is safe to preempt execution
- * when CONFIG_PREEMPT=n
- */
-#define ACPI_PREEMPTION_POINT() \
-	do { \
-		if (!irqs_disabled()) \
-			cond_resched(); \
-	} while (0)
-
-#endif
-
 /*
  * When lockdep is enabled, the spin_lock_init() macro stringifies it's
  * argument and uses that as a name for the lock in debugging.