Changes after my own PR review

asusctl/src/aura_cli.rs

@@ -88,15 +88,15 @@ impl FromStr for LedBrightness {
         }
     }
 }
-impl Display for LedBrightness {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+impl ToString for LedBrightness {
+    fn to_string(&self) -> String {
         let s = match self.level {
             Some(0x00) => "low",
             Some(0x01) => "med",
             Some(0x02) => "high",
             _ => "unknown",
         };
-        write!(f, "{}", s.to_owned())
+        s.to_owned()
     }
 }