* Make hexdigits a global constant

(cherry picked from commit b1412ec5c036fcd2a1119ae17952f87caa792375)

rtl/objpas/sysutils/sysstr.inc

@@ -1,3 +1,4 @@
+
 {
     *********************************************************************
     Copyright (C) 1997, 1998 Gertjan Schouten
@@ -876,9 +877,6 @@ end;
 
 {   IntToHex returns a string representing the hexadecimal value of Value   }
 
-const
-   HexDigits: array[0..15] of char = '0123456789ABCDEF';
-
 function IntToHex(Value: Longint; Digits: integer): string;
 var i: integer;
 begin