who: hardcode idle current/unknown placeholders

Author: sylvestre

src/uu/who/locales/en-US.ftl

@@ -32,9 +32,7 @@ who-user-count = # { $count ->
 }
 
 # Idle time indicators
-who-idle-current =   .
 who-idle-old =  old
-who-idle-unknown =   ?
 
 # System information
 who-runlevel = run-level { $level }

src/uu/who/locales/fr-FR.ftl

@@ -32,7 +32,6 @@ who-user-count = # { $count ->
 
 # Idle time indicators
 who-idle-old = anc.
-who-idle-unknown =   ?
 
 # System information
 who-runlevel = niveau-exec { $level }

src/uu/who/src/platform/unix.rs

@@ -379,7 +379,7 @@ impl Who {
         }
 
         let idle = if last_change == 0 {
-            translate!("who-idle-unknown").into()
+            "  ?".into()
         } else {
             idle_string(last_change, 0)
         };