ACPICA: Update to GPIO region handler interface.

Changes to correct several GPIO issues:

1) The update_rule in a GPIO field definition is now ignored;
a read-modify-write operation is never performed for GPIO fields.
(Internally, this means that the field assembly/disassembly
code is completely bypassed for GPIO.)

2) The Address parameter passed to a GPIO region handler is
now the bit offset of the field from a previous Connection()
operator. Thus, it becomes a "Pin Number Index" into the
Connection() resource descriptor.

3) The bit_width parameter passed to a GPIO region handler is
now the exact bit width of the GPIO field. Thus, it can be
interpreted as "number of pins".

Overall, we can now say that the region handler interface
to GPIO handlers is a raw "bit/pin" addressed interface, not
a byte-addressed interface like the system_memory handler interface.

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Cc: 3.15+ <stable@vger.kernel.org> # 3.15+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/acpi/acpica/acobject.h

@@ -264,6 +264,7 @@ struct acpi_object_region_field {
 	ACPI_OBJECT_COMMON_HEADER ACPI_COMMON_FIELD_INFO u16 resource_length;
 	union acpi_operand_object *region_obj;	/* Containing op_region object */
 	u8 *resource_buffer;	/* resource_template for serial regions/fields */
+	u16 pin_number_index;	/* Index relative to previous Connection/Template */
 };
 
 struct acpi_object_bank_field {