Fix bugs with preflight check and DPDK dependency

Fix bugs with preflight check and DPDK dependency

Remove preflight check for isolcpus as this breaks libvirt (VM) deployments
Update DPDK dependency on meson as v0.60.0 breaks build process

Signed-off-by: Michael Pedersen <michaelx.pedersen@intel.com>
Change-Id: I5f0a46c80c88958437b7ab8c34de5fefc337de60
Reviewed-on: https://gerrit.opnfv.org/gerrit/c/kuberef/+/72991
Tested-by: jenkins-ci <jenkins-opnfv-ci@opnfv.org>
Reviewed-by: Rihab Banday <rihab.banday@ericsson.com>
Reviewed-by: Georg Kunz <georg.kunz@ericsson.com>