Med: oracledb.sh: Remove quotes around listener name

Remove quotes around the listener name variable in calls to lsnrctl.
The quotes caused the commands to fail when a listener name was not
specified in the cluster configuration.

Signed-off-by: Ryan McCabe <rmccabe@redhat.com>
Merge pull request #341 from ryan-mccabe/master

Med: oracledb.sh: Remove quotes around listener name