[Ada] Remove repeated analysis for pragma Thread_Local_Storage

[Pierre-Marie de Rodat via Gcc-patches]

When analysing pragma Thread_Local_Storage its argument is analysed by
the call to Check_Arg_Is_Library_Level_Local_Name. There is no need to
reanalyse it. Code cleanup; behaviour is not affected.

Tested on x86_64-pc-linux-gnu, committed on trunk

gcc/ada/

        * sem_prag.adb (Analyze_Pragma): Remove unnecessary call to
        Analyze.
diff --git a/gcc/ada/sem_prag.adb b/gcc/ada/sem_prag.adb
--- a/gcc/ada/sem_prag.adb
+++ b/gcc/ada/sem_prag.adb
@@ -24861,7 +24861,6 @@ package body Sem_Prag is
             Check_Arg_Is_Library_Level_Local_Name (Arg1);
 
             Id := Get_Pragma_Arg (Arg1);
-            Analyze (Id);
 
             if not Is_Entity_Name (Id)
               or else Ekind (Entity (Id)) /= E_Variable