drm/i915/bios: remove the raw version of child device config

Convert the only user of the raw field, switching to the recently added
struct fields. No functional changes.

Cc: Animesh Manna <animesh.manna@intel.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/83e6a2058553a43e0d08a49df1f86821f38b206b.1503600621.git.jani.nikula@intel.com

drivers/gpu/drm/i915/intel_bios.c

@@ -1210,7 +1210,7 @@ static void parse_ddi_port(struct drm_i915_private *dev_priv, enum port port,
 
 	if (bdb->version >= 158) {
 		/* The VBT HDMI level shift values match the table we have. */
-		hdmi_level_shift = child->raw[7] & 0xF;
+		hdmi_level_shift = child->common.hdmi_level_shifter_value;
 		DRM_DEBUG_KMS("VBT HDMI level shift for port %c: %d\n",
 			      port_name(port),
 			      hdmi_level_shift);

drivers/gpu/drm/i915/intel_vbt_defs.h

@@ -312,9 +312,6 @@ struct common_child_dev_config {
 /* This field changes depending on the BDB version, so the most reliable way to
  * read it is by checking the BDB version and reading the raw pointer. */
 union child_device_config {
-	/* This one is safe to be used anywhere, but the code should still check
-	 * the BDB version. */
-	u8 raw[33];
 	/* This one should only be kept for legacy code. */
 	struct old_child_dev_config old;
 	/* This one should also be safe to use anywhere, even without version