Hive services need HADOOP_CLIENT_OPTS for proper log4j2 initialization

HIVE-12497 removed HADOOP_CLIENT_OPTS as it slowed down cli launch time. But it leads to log4j2 not being initialized when using services other than CLI. Other services like metastore, schematool etc. rely on log4j to initialize the logging based on the presence of log4j2.properties file in the classpath. If we use the standard name for log4j configuration file (log4j2.properties) then automatic initialization will happen. If not, we have to tell log4j to look for specific properties file. This is done via -Dlog4j.configurationFile system property. If we pass this system property via HADOOP_CLIENT_OPTS then all hive services will have logging initialized properly.

In HIVE-12497, the problem was we had HADOOP_CLIENT_OPTS at the top of the script. As a result, hadoop and hbase commands tries to initialize logging which took long time slowing down the startup time.