ACPICA: Disassembler: Fix for gpio_int interrupt polarity flags.

The field is actually 2 bits, not 1.

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>