删除无用代码

git-svn-id: http://code.alibabatech.com/svn/druid/trunk@127 b9813039-fb51-4c41-a8b9-e21c2acb5095

src/main/java/com/alibaba/druid/sql/parser/Lexer.java

@@ -248,7 +248,7 @@ public class Lexer {
                     throw new SQLParseException("TODO"); // TODO
                 case '@':
                     scanVariable();
-                    token = Token.USR_VAR;
+                    token = Token.VARIANT;
                     return;
                 case '/':
                     scanComment();