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 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
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"