[DOCS] Fixed misleading documentation on Impala + HDFS caching
[DOCS] Fixed misleading documentation on Impala + HDFS caching

Change-Id: I63cd1ff7b885a094a4a3e91c31101d25414b4db7
Reviewed-on: http://gerrit.cloudera.org:8080/10454
Reviewed-by: Tim Armstrong <2f8e34250f03a653da3dc27f7ec203eafdde80fc@cloudera.com>
Tested-by: Impala Public Jenkins <039b6b20426ff68ebe492b3021890d8c8fd010c9@cloudera.com>

cloudera/Impala,cloudera/Impala,cloudera/Impala,cloudera/Impala,cloudera/Impala,cloudera/Impala,cloudera/Impala