ACPICA: Simplify configuration of global ACPI_REDUCED_HARDWARE macro.

Surround definition of this with a #ifndef so that the kernel
can define it elsewhere if desired.

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

include/acpi/acconfig.h

@@ -100,7 +100,9 @@
  *      ACPI PM timer
  *      FACS table (Waking vectors and Global Lock)
  */
+#ifndef ACPI_REDUCED_HARDWARE
 #define ACPI_REDUCED_HARDWARE           FALSE
+#endif
 
 /******************************************************************************
  *