[SPARK-5696] [SQL] [HOTFIX] Asks HiveThriftServer2 to re-initialize log4j using Hive configurations

In this way, log4j configurations overriden by jets3t-0.9.2.jar can be again overriden by Hive default log4j configurations.

This might not be the best solution for this issue since it requires users to use `hive-log4j.properties` rather than `log4j.properties` to initialize `HiveThriftServer2` logging configurations, which can be confusing. The main purpose of this PR is to fix Jenkins PR build.

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Author: Cheng Lian <lian@databricks.com>

Closes #4484 from liancheng/spark-5696 and squashes the following commits:

df83956 [Cheng Lian] Hot fix: asks HiveThriftServer2 to re-initialize log4j using Hive configurations

sql/hive-thriftserver/src/main/scala/org/apache/spark/sql/hive/thriftserver/HiveThriftServer2.scala

@@ -18,6 +18,7 @@
 package org.apache.spark.sql.hive.thriftserver
 
 import org.apache.commons.logging.LogFactory
+import org.apache.hadoop.hive.common.LogUtils
 import org.apache.hadoop.hive.conf.HiveConf
 import org.apache.hadoop.hive.conf.HiveConf.ConfVars
 import org.apache.hive.service.cli.thrift.{ThriftBinaryCLIService, ThriftHttpCLIService}
@@ -54,6 +55,8 @@ object HiveThriftServer2 extends Logging {
       System.exit(-1)
     }
 
+    LogUtils.initHiveLog4j()
+
     logInfo("Starting SparkContext")
     SparkSQLEnv.init()