* after upgrading to gcc-8, seems dpdk requires more settings to compile.
in which, CONFIG_RTE_MAX_VFIO_GROUPS=64 is copied from config/common_base.
* librte_bus_pci.a depends on librte_pci.a, so reorder the libraries
in DPDK_LIBRARIES.
Signed-off-by: Kefu Chai <kchai@redhat.com>