Disable collection of IF-MAP metric

In larger environments, querying IF-MAP takes too much time (up to
several minutes per call) and puts too much load on the IF-MAP server.
This change disables the collection of the contrail_ifmap_count metric
since it isn't used anywhere (neither dashboards nor alerts).

Change-Id: Ia86892921e93ec5b3a70115811659002b45ab503
2 files changed