ACPICA: Support for custom ACPICA build for ACPI 5 reduced hardware

Add ACPI_REDUCED_HARDWARE flag that removes all hardware-related
code (about 10% code, 5% static data).

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/acpica/evgpeutil.c b/drivers/acpi/acpica/evgpeutil.c
index 2507393..3c43796 100644
--- a/drivers/acpi/acpica/evgpeutil.c
+++ b/drivers/acpi/acpica/evgpeutil.c
@@ -48,6 +48,7 @@
 #define _COMPONENT          ACPI_EVENTS
 ACPI_MODULE_NAME("evgpeutil")
 
+#if (!ACPI_REDUCED_HARDWARE)	/* Entire module */
 /*******************************************************************************
  *
  * FUNCTION:    acpi_ev_walk_gpe_list
@@ -374,3 +375,5 @@
 
 	return_ACPI_STATUS(AE_OK);
 }
+
+#endif				/* !ACPI_REDUCED_HARDWARE */