ACPICA: New: acpi_get_gpe_device interface

This function maps an input GPE index to a GPE block device. Also
Added acpi_current_gpe_count to track the current number of GPEs
that are being managed by the ACPICA core (both FADT-based GPEs
and the GPEs contained in GPE block devices.)

Modify drivers/acpi/system.c to use these 2 new interfaces

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/include/acpi/acevents.h b/include/acpi/acevents.h
index d5d099b..07e2013 100644
--- a/include/acpi/acevents.h
+++ b/include/acpi/acevents.h
@@ -93,11 +93,13 @@
  */
 u8 acpi_ev_valid_gpe_event(struct acpi_gpe_event_info *gpe_event_info);
 
-acpi_status acpi_ev_walk_gpe_list(acpi_gpe_callback gpe_walk_callback);
+acpi_status
+acpi_ev_walk_gpe_list(acpi_gpe_callback gpe_walk_callback, void *context);
 
 acpi_status
 acpi_ev_delete_gpe_handlers(struct acpi_gpe_xrupt_info *gpe_xrupt_info,
-			    struct acpi_gpe_block_info *gpe_block);
+			    struct acpi_gpe_block_info *gpe_block,
+			    void *context);
 
 acpi_status
 acpi_ev_create_gpe_block(struct acpi_namespace_node *gpe_device,