THRIFT-3668 range check error in compact protocol

Client: Delphi
Patch: Jens Geyer

Author: Jens-G

lib/delphi/src/Thrift.Protocol.Compact.pas

@@ -801,7 +801,7 @@ function TCompactProtocolImpl.ReadByte: ShortInt;
 begin
   SetLength( data, 1);
   Transport.ReadAll( data, 0, 1);
-  result := data[0];
+  result := ShortInt(data[0]);
 end;