xenserver: updated xen-bugtool to XenServer trunk version.
The version of xen-bugtool include in openvswitch.git was forked long
ago from the xenserver version. Pull up to the version taken from
XenServer's trunk branch just after the integration of
22c75d593 from
openvswitch.git.
I tested that core and log files as well as ovs-dpctl {show,dump-flows}
and ovs-ofctl {show,dump-flows,status} are picked up correctly after the
big vswitch->openvswitch renaming.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>