bus/pci: assign driver pointer before mapping

bus/pci: assign driver pointer before mapping

Patch changing the way of accessing interrupt handle also changed order
of the rte_pci_map_device() call and rte_pci_device:driver assignment.
It was causing issues with Write Combine mapping on the Linux platform
if it was used with the igb_uio module.

Linux implementation of pci_uio_map_resource_by_index(), which is called
by rte_pci_map_device(), needs access to the device's driver. Otherwise
it won't be able to check the driver's flags and won't respect them.

Fixes: d61138d4f0e2 ("drivers: remove direct access to interrupt handle")
Cc: stable@dpdk.org
Signed-off-by: Michal Krawczyk <mk@semihalf.com>