enc28j60: Remove duplicate messaging

The ->probe() and ->remove() stages can be easily debugged with
initcall_debug or function tracer. There is no need to repeat the same
explicitly in the driver.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>