Replace Alog_Default_Level with Log_Level'First

Instead of declaring a constant with a more or less arbitrary value use
Log_Level'First instead.

src/alog-policy_db-types.adb

@@ -98,7 +98,7 @@ package body Alog.Policy_DB.Types is
       procedure Reset
       is
       begin
-         Current_Default_Loglevel := Alog_Default_Level;
+         Current_Default_Loglevel := Log_Level'First;
          Ident_Levels.Clear;
       end Reset;
 

src/alog-policy_db-types.ads

@@ -90,7 +90,7 @@ package Alog.Policy_DB.Types is
       Ident_Levels : Maps.Wildcard_Level_Map;
       --  Identifier based loglevels.
 
-      Current_Default_Loglevel : Log_Level := Alog_Default_Level;
+      Current_Default_Loglevel : Log_Level := Log_Level'First;
       --  Current default loglevel.
    end Protected_Policy_DB;
 

src/alog-policy_db.ads

@@ -26,9 +26,6 @@ with Alog.Maps;
 --  in the database are used inside the framework for logging decisions.
 package Alog.Policy_DB is
 
-   Alog_Default_Level : constant Log_Level := Info;
-   --  Framework default loglevel.
-
    procedure Set_Default_Loglevel (Level : Log_Level);
    --  Set given loglevel as default loglevel.
 

tests/policy_tests.adb

@@ -134,7 +134,7 @@ package body Policy_Tests is
 
       DB.Reset;
 
-      Assert (Condition => DB.Get_Default_Loglevel = DB.Alog_Default_Level,
+      Assert (Condition => DB.Get_Default_Loglevel = Log_Level'First,
               Message   => "Default loglevel mismatch");
 
       declare