net: phy: dp83822: Fix NULL pointer dereference on DP83825 devices

In the Linux kernel, the following vulnerability has been resolved:

net: phy: dp83822: Fix NULL pointer dereference on DP83825 devices

The probe() function is only used for DP83822 and DP83826 PHY,

leaving the private data pointer uninitialized for the DP83825 models

which causes a NULL pointer dereference in the recently introduced/changed

functions dp8382x_config_init() and dp83822_set_wol().

Add the dp8382x_probe() function, so all PHY models will have a valid

private data pointer to fix this issue and also prevent similar issues

in the future.