Only build OVS when necessary or specified by -f
Only build OVS when necessary or specified by -f

Change-Id: Ib156069beb3ea21c0b352c7212d9a0fd1e711f25
Signed-off-by: Scott Mann <38e162d3d4b879610bb9152c7a5a8299f9617edb@noironetworks.com>

opendaylight/opflex,mhrobinson/opflex,mhrobinson/opflex,opendaylight/opflex,mhrobinson/opflex,opendaylight/opflex,mhrobinson/opflex,opendaylight/opflex