libnvdimm, bus: Check id immediately following ida_simple_get

The id check was not executed immediately following ida_simple_get. Just
change the codes position, without function change.

Signed-off-by: Ocean He <hehy1@lenovo.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>