r8152: move some functions from probe to open

Add up method for rtl_ops and asign relative functions. Move
clear_bp() and hw_phy_cfg() from init method to up method of rtl_ops.
Call rtl_ops.up() for ndo_open() and rtl_ops.down for ndo_stop().

Replace allocating the memory in probe() with in ndo_open().

Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>