Update xeniface to #10

[CA-119964] Remove a null dereferece which causes an exception

Signed-off-by: Ben Chalmers <Ben.Chalmers@citrix.com>
Merge pull request #32 from benchalmers/ca-119964

Update xeniface to #10

Approved-By: Ben Chalmers <Ben.Chalmers@citrix.com>