drm/i915: Change I2C api to pass around i2c_adapters

The existing API passed around intel_i2c_chan pointers, which are dependent
on the i2c bit-banging algo. This precluded the driver from using outputs
which use a different algo. Switching to the more general i2c_adpater allows
the driver to support non bit-banging DDC.

This also required moving the slave address into the output private
structures.

Signed-off-by: Keith Packard <keithp@keithp.com>
diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c
index 2495359..fbe9600 100644
--- a/drivers/gpu/drm/i915/intel_hdmi.c
+++ b/drivers/gpu/drm/i915/intel_hdmi.c
@@ -139,7 +139,7 @@
 	enum drm_connector_status status = connector_status_disconnected;
 
 	edid = drm_get_edid(&intel_output->base,
-			    &intel_output->ddc_bus->adapter);
+			    intel_output->ddc_bus);
 	hdmi_priv->has_hdmi_sink = false;
 	if (edid) {
 		if (edid->digital) {