phy: ti: Init node before reading

There is a need to fill node before clk_output_sel is setup.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Siva Durga Prasad Paladugu <siva.durga.paladugu@xilinx.com>
Reviewed-by:  <hannes.schmelzer@br-automation.com>