Allow multiple bridges

Previously bridges were hard coded to port 0 so only one could
exist. This patch generalises the current vport arrangement to
work with bridges, i.e. bridges are assigned a unique port number
within a range. However we still have no "real" bridge & any pkts
sent to a bridge (or to LOCAL) will be dropped.

Reviewed-By: stephen.finucane@intel.com
Reviewed-By: meghan.halton@intel.com

Signed-off-by: Eimear Morrissey <eimear.morrissey@intel.com>
datapath/dpdk: add missing check target to Makefile

Add missing "check" target to Makefile that causes building errors
when running unit tests.

Change-Id: If28f6ec9fd1e225aba131d7652f1cf502ef4036b
Signed-off-by: Nicolas Pernas Maradei <nicolasx.pernas.maradei@intel.com>
Reviewed-by: Mark D. Gray <mark.d.gray@intel.com>