asoc: exynos: hdmi-audio use platform data for hpd gpio information

asoc: exynos: hdmi-audio use platform data for hpd gpio information

With this patch, hdmi-audio driver gets the gpio pin number from
platform data instead of getting from device tree. Due to that
of_get_named_gpio_flags was resetting the pin function to hpd
instead of external interrupt. This breaks the hotplug detection.

BUG=chrome-os-partner:15274
TEST=1) Boot with/without hdmi plugged.
2) S2R scenarios.
3) Audio playback with hpd scenarios.

Change-Id: I592942347040003cfe550f97436dacc5aa73a95f
Signed-off-by: Rahul Sharma <rahul.sharma@samsung.com>
Reviewed-on: https://gerrit.chromium.org/gerrit/35514
Commit-Ready: Doug Anderson <dianders@chromium.org>
Reviewed-by: Doug Anderson <dianders@chromium.org>