[dpdk-dev] UIO pci-generic support broke igb_uio

[Stephen Hemminger <stephen@networkplumber.org>]

The addition of uio pci-generic broke use if igb_uio because
the wrong file descriptor is being used.

If I was a hard ass I would recommend uio pci-generic support
be reverted from 2.0 until/unless this fixed.

Failure mode is on startup:

EAL:  Error reading interrupts status for fd 0
PANIC in start_port()
rte_eth-dev_start: port=0 err=-5

The problem commit is:
commit 4a499c64959074ba6fa6a5a2b3a2a6aa10627fa1
Author: Danny Zhou <danny.zhou@intel.com>
Date:   Fri Feb 20 16:59:15 2015 +0000

    eal/linux: enable uio_pci_generic support
    
    Change the EAL PCI code so that it can work with both the
    uio_pci_generic in-tree driver, as well as the igb_uio
    DPDK-specific driver.
    
    This involves changes to
    1) Modify method of retrieving BAR resource mapping information
    2) Mapping using resource files in /sys rather than /dev/uio*
    2) Setup bus master bit in NIC's PCIe configuration space for
    uio_pci_generic.
    
    Signed-off-by: Danny Zhou <danny.zhou@intel.com>
    Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
    Acked-by: Declan Doherty <declan.doherty@intel.com>