netapp_pool_name_search_pattern doesn't accept regex

[Jonathan Williams]

This is an issue observed with:

* Cinder
* Multiple versions of Openstack from Stein to Train

When filtering available pools using 'netapp_pool_name_search_pattern' in cinder.conf, you're limited on what you can actually use as it doesn't seem that regex pattern matching works. The
documentation indicates that regular expressions are supported.

What works is:
netapp_pool_name_search_pattern=(openstack_iscsi_backing_01)
netapp_pool_name_search_pattern=(openstack_iscsi_backing_01|openstack_iscsi_backing_02| openstack_iscsi_backing_03)

You have to specify the exact 'pool_name' as reported by cinder get-pools --detail.

What does not work:
netapp_pool_name_search_pattern=(openstack)
netapp_pool_name_search_pattern=(openstack_*)

I've been able to reproduce this in my lab environments and I've had a couple of customers
generate cases for this issue.