docs: Address master-of-zen#836

av1an/src/main.rs

@@ -379,7 +379,7 @@ pub struct CliOpts {
   /// Photon noise tables are more visually pleasing than the film grain generated by aomenc,
   /// and provide a consistent level of grain regardless of the level of grain in the source.
   /// Strength values correlate to ISO values, e.g. 1 = ISO 100, and 64 = ISO 6400. This
-  /// option currently only supports aomenc and rav1e.
+  /// option is only implemented in select AV1 encoders, including aomenc, rav1e and svt-av1.
   ///
   /// An encoder's grain synthesis will still work without using this option, by specifying the
   /// correct parameter to the encoder. However, the two should not be used together,