Call ironic-dbsync with proper --config-file option

Without --config-file option ironic-dbsync creates SQLite database
in the current directory, instead of migrating MySQL database.

Change-Id: Ib733dbf9198a037114f6221e974acb29d109ff22
Merge "Call ironic-dbsync with proper --config-file option"
Merge branch 'master' of github.com:openstack-dev/devstack