net/nfp: support PF devices inside PMD initialization

net/nfp: support PF devices inside PMD initialization

nfp_net_init is where a dpdk port related to a eth_dev is initialized.
NFP VF vNICs use VF PCI BARs as they come after SRIOV is enabled. But for
NFP PF vNIC just a subset of PF PCI BARs are used.

This patch adds support for mapping the right PCI BAR subsets for the PF
vNIC. It uses the NSPU API functions introduced previously for configuring
NFP expansion bars.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>