Without this change some services for ceilometer will not start
breaking CI.
This change I7447ba4f408c95b0acf1b809504ce16fff1c6e21 was validated
against the ceilometer devstack plugin but apparently not against
devstack itself. Until I413ab159474b7d7231ad66d3a482201f74efe8a8
merges devstack still has ceilometer support and is used in the
gate.
Change-Id: Ib1ea8b6ef7019570f82b0ba87e03fc627c8f6801