[RFC, PATCH 0/4] net: sh_eth: modify for both modules

This current driver supports ETHER and GETHER. But we cannot
use them at same time because the defination of registers is
hardcoded by #ifdef in sh_eth.h.
The patches modify the defination to arrays of const. Then
we can choose the array by platform_device's data.
The patches also modify for GETHER. The current driver used
the "#ifdef CONFIG_CPU_SUBTYPE_SH7763". The patches remove it
and check by other method for GETHER.