drm/i915/bios: move aux ch and ddc checks at a lower level

Unify the code paths at the higher level.
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/44559ef456015f65a863c3d89a9bea9157d13a05.1615998927.git.jani.nikula@intel.com

drivers/gpu/drm/i915/display/intel_bios.c

@@ -1505,6 +1505,9 @@ static enum port get_port_by_ddc_pin(struct drm_i915_private *i915, u8 ddc_pin)
 	const struct ddi_vbt_port_info *info;
 	enum port port;
 
+	if (!ddc_pin)
+		return PORT_NONE;
+
 	for_each_port(port) {
 		info = &i915->vbt.ddi_port_info[port];
 
@@ -1521,9 +1524,6 @@ static void sanitize_ddc_pin(struct drm_i915_private *i915,
 	struct ddi_vbt_port_info *info = &i915->vbt.ddi_port_info[port];
 	enum port p;
 
-	if (!info->alternate_ddc_pin)
-		return;
-
 	p = get_port_by_ddc_pin(i915, info->alternate_ddc_pin);
 	if (p == PORT_NONE)
 		return;
@@ -1555,6 +1555,9 @@ static enum port get_port_by_aux_ch(struct drm_i915_private *i915, u8 aux_ch)
 	const struct ddi_vbt_port_info *info;
 	enum port port;
 
+	if (!aux_ch)
+		return PORT_NONE;
+
 	for_each_port(port) {
 		info = &i915->vbt.ddi_port_info[port];
 
@@ -1571,9 +1574,6 @@ static void sanitize_aux_ch(struct drm_i915_private *i915,
 	struct ddi_vbt_port_info *info = &i915->vbt.ddi_port_info[port];
 	enum port p;
 
-	if (!info->alternate_aux_channel)
-		return;
-
 	p = get_port_by_aux_ch(i915, info->alternate_aux_channel);
 	if (p == PORT_NONE)
 		return;