drm/i915/tv: use DISPLAY_VER instead of GRAPHICS_VER

Display code should not care about graphics version. It's only comments
here, but update anyway.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240104174350.823605-5-jani.nikula@intel.com

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

@@ -1327,7 +1327,7 @@ intel_tv_compute_config(struct intel_encoder *encoder,
 	 * the active portion. Hence following this formula seems
 	 * more trouble that it's worth.
 	 *
-	 * if (GRAPHICS_VER(dev_priv) == 4) {
+	 * if (DISPLAY_VER(dev_priv) == 4) {
 	 *	num = cdclk * (tv_mode->oversample >> !tv_mode->progressive);
 	 *	den = tv_mode->clock;
 	 * } else {