Use oslo.db library

oslo.db library has been graduated from oslo-incubator,
so now we can use it instead of ironic.openstack.common.db.* code.

Co-Authored-By: Ghe Rivero <ghe.rivero@hp.com>

Implements: blueprint oslo.db

Change-Id: I250050a7dbd8735ba3af954223b54eabae793f59
Use opportunistic approach for migration testing

Refactored migration tests due to use OpportunisticTestCase, removed
unused code and ``test_migrations.conf`` file.

This change allows tests use database ``openstack_citest`` only
for connection to the database backend. The main feature of this
approach is - for each migration test will be created new database
with random name. This will avoid migration tests of race conditions
and reduce tests intersection.

``test_migrations.conf`` file was removed, because we create test
database for migration test, so we no longer need test database credentials.

Closes-Bug: #1327397
Closes-Bug: #1328997

Change-Id: I95ad140ba5f483cd3dc36e2b78f140826d57624f
Use mock.assert_called_once_with()

One of the ilo unit tests makes a call to Mock.assert_once_called_with().
That doesn't exist. It should be Mock.assert_called_once_with().

Change-Id: I7b57483479ddcd5ae00122064f8d4a133e922ae7
IPMITool to use the new ManagementInterface

Add the new ManagementInterface to the IPMITool driver. The method
set_boot_device was removed from the VendorPassthru interface because
this method was promoved to the ManagementInterface.

Implements: blueprint new-management-interface
Change-Id: I7bd9cb0a5d38f1044ae3e74dd08564e20828933b
Factor out deploy info from PXE driver

This factors the code to get the deploy kernel and ramdisk info out
of the PXE driver, as this can be shared between the PXE and agent
drivers.

Change-Id: I2c3722d091f02259aa9e6cabebaabf25eead8bc2
(cherry picked from commit 8368bf9c66eea3a5f4706c867e266e00a5886213)
Merge "Factor out deploy info from PXE driver"
Merge "Use oslo.db library"
Merge "Use opportunistic approach for migration testing"
Merge "IPMITool to use the new ManagementInterface"