xen/pciback: remove duplicated #include

Remove duplicated #include('s) in
  drivers/xen/xen-pciback/xenbus.c

Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
1 file changed