[Ada] Add more dummy names in Sem_Warn.Has_Junk_Name

To sync the names used in CodePeer (and SPARK) when filtering out
warnings on e.g. unused variables.

gcc/ada/

	* sem_warn.adb (Has_Junk_Name): Add more dummy names.

gcc/ada/sem_warn.adb

@@ -2872,7 +2872,9 @@ package body Sem_Warn is
         Match ("dummy")   or else
         Match ("ignore")  or else
         Match ("junk")    or else
-        Match ("unused");
+        Match ("unuse")   or else
+        Match ("tmp")     or else
+        Match ("temp");
    end Has_Junk_Name;
 
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