drm/i915: Rename SNB/IVB CPU eDP signal level funcs

To make the intent more clear, let's rename the signal level funcs for
the SNB/IVB CPU eDP.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180517170309.28630-4-ville.syrjala@linux.intel.comReviewed-by: NJani Nikula <jani.nikula@intel.com>

drivers/gpu/drm/i915/intel_dp.c

@@ -3488,9 +3488,9 @@ gen4_signal_levels(uint8_t train_set)
 	return signal_levels;
 }
 
-/* Gen6's DP voltage swing and pre-emphasis control */
+/* SNB CPU eDP voltage swing and pre-emphasis control */
 static uint32_t
-gen6_edp_signal_levels(uint8_t train_set)
+snb_cpu_edp_signal_levels(uint8_t train_set)
 {
 	int signal_levels = train_set & (DP_TRAIN_VOLTAGE_SWING_MASK |
 					 DP_TRAIN_PRE_EMPHASIS_MASK);
@@ -3516,9 +3516,9 @@ gen6_edp_signal_levels(uint8_t train_set)
 	}
 }
 
-/* Gen7's DP voltage swing and pre-emphasis control */
+/* IVB CPU eDP voltage swing and pre-emphasis control */
 static uint32_t
-gen7_edp_signal_levels(uint8_t train_set)
+ivb_cpu_edp_signal_levels(uint8_t train_set)
 {
 	int signal_levels = train_set & (DP_TRAIN_VOLTAGE_SWING_MASK |
 					 DP_TRAIN_PRE_EMPHASIS_MASK);
@@ -3566,10 +3566,10 @@ intel_dp_set_signal_levels(struct intel_dp *intel_dp)
 	} else if (IS_VALLEYVIEW(dev_priv)) {
 		signal_levels = vlv_signal_levels(intel_dp);
 	} else if (IS_IVYBRIDGE(dev_priv) && port == PORT_A) {
-		signal_levels = gen7_edp_signal_levels(train_set);
+		signal_levels = ivb_cpu_edp_signal_levels(train_set);
 		mask = EDP_LINK_TRAIN_VOL_EMP_MASK_IVB;
 	} else if (IS_GEN6(dev_priv) && port == PORT_A) {
-		signal_levels = gen6_edp_signal_levels(train_set);
+		signal_levels = snb_cpu_edp_signal_levels(train_set);
 		mask = EDP_LINK_TRAIN_VOL_EMP_MASK_SNB;
 	} else {
 		signal_levels = gen4_signal_levels(train_set);