usertools: support globbing for PCI device binding

usertools: support globbing for PCI device binding

When binding or unbinding a range of devices, it can be useful to use
wildcards to specify the devices rather than repeating the same prefix
multiple times. We can use the python "glob" module to give us this
functionality - at least for PCI devices - by checking /sys for matching
files.

Examples of use from my system:

    ./dpdk-devbind.py -b vfio-pci 80:04.*
    ./dpdk-devbind.py -u 80:04.[2-7]

The first example binds eight devices, 80:04.0..80:04.7, to vfio-pci. The
second then unbinds six of those devices, 80:04.2..80:04.7, from any
driver.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
Acked-by: Anatoly Burakov <anatoly.burakov@intel.com>
Tested-by: Ferruh Yigit <ferruh.yigit@intel.com>