ethernet: realtek: use module_pci_driver

This patch converts to use the macro module_pci_driver, which makes
the code smaller and simpler.

Previously in this driver we are having driver version info will be
printed log buffer based on whether the driver selected as module
or statically into image itself. By using the module_pci_driver that
part of the code removed. For the first time of the device init,
we are making the version info to be printed once.

Signed-off-by: Varka Bhadram <varkab@cdac.in>
Signed-off-by: David S. Miller <davem@davemloft.net>