For oracle database, the usage of REGEXP is not correct for List Servers by filter.

[Qing Xin Meng]

The REGEXP_LIKE operator for oracle db backend is not correct.

For the MySql database, the following SQL syntax is right:
---
select xxx from xxx where column REGEXP pattern
---

But for Oracle database, the following SQL syntax is not right:
---
select xxx from xxx where column REGEXP_LIKE pattern
---

It should be:
---
select xxx from xxx where REGEXP_LIKE (column, pattern)
---

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/45026
Committed: http://github.com/openstack/nova/commit/3dad53ce1d0263786c3f9ff585dc446a0a9dbecf
Submitter: Jenkins
Branch: master

commit 3dad53ce1d0263786c3f9ff585dc446a0a9dbecf
Author: QingXin Meng <email address hidden>
Date: Wed Sep 4 01:52:53 2013 -0700

    Code change for regex filter matching

    Remove REGEXP_LIKE operator for oracle db backend since it's not suitable,
    Such as:
    Oracle: 'select xxx from xxx where REGEXP_LIKE (column, pattern)'
    Mysql: 'select xxx from xxx where column REGEXP pattern'

    For the simple pattern matching(LIKE operator) used for unsupported backend db,
    add '%' wildcard character on both sides of the value.

    Change-Id: I4682d38086a06032bb5650a14b253f6b2b859613
    Closes-Bug: #1230102