ASoC: Intel: bytcr_rt5651: Add support for jack-detect using an external GPIO

Some board designs hook the jack-detect up to an external GPIO, rather
then to one of the codec pins, add support for this.

Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mark Brown <broonie@kernel.org>