eliminate the need for hp3parclient in tests

In order to eliminate the need to have the hp3parclient in the
global-requirements project, we need to remove the hp3parclient
from being imported in all 3par driver unit tests in cinder.

Closes-Bug: #1315195
Change-Id: Ife5c70871e742be5970be8f0284e12554f93cab4
Merge "eliminate the need for hp3parclient in tests"