xend: pass-through: Only call setupOneDevice() once per device

xend: pass-through: Only call setupOneDevice() once per device

As observed by Dexuan Cui, when PCI devices are passed through at
domain-creation-time setupOneDevice() will be called twice.

Once via setupDevice() and once via econfigureDevice() which
is called in pci_device_configure().

This patch removes the first of these.

Cc: Dexuan Cui <dexuan.cui@intel.com>
Cc: Masaki Kanno <kanno.masaki@jp.fujitsu.com>
Signed-off-by: Simon Horman <horms@verge.net.au>