arm64: zynqmp: add "xlnx,nr-outputs" property for clk_wiz_0 node

In clk-xlnx-clock-wizard.c, the function clk_wzrd_probe will check if
there is "xlnx,nr-outputs" property, if not, the probe will return
error. Add "xlnx,nr-outputs" property for clk_wiz_0 node to avoid probe
failure.

Signed-off-by: Quanyang Wang <quanyang.wang@windriver.com>
Signed-off-by: Bruce Ashfield <bruce.ashfield@gmail.com>