sh_eth: get R8A777x support out of #ifdef

Get the R-Car code/data in the driver out of #ifdef by adding "r8a777x-ether" to
the platfrom driver's  ID table; since it's the last #ifdef, we remove CARDNAME
from the  ID table and no longer check  the driver data before  assigning it to
'mdp->cd'...
Change the Ether platform device's name in the ARM platform code accordingly.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>