HIVE-8187: CBO: Change Optiq Type System Precision/scale to use Hive Type System Precision/Scale (Laljo John Pullokkaran via Gunther Hagleitner)

git-svn-id: https://svn.apache.org/repos/asf/hive/branches/cbo@1626120 13f79535-47bb-0310-9956-ffa450edef68