sh_eth: TSU_QTAG0/1 registers the same as TSU_QTAGM0/1

The TSU_QTAG0/1 registers found in the Gigabit Ether controllers actually
have the same long name  as the TSU_QTAGM0/1 registers in the early Ether
controllers:  Qtag Addition/Deletion Set Register (Port 0/1 to 1/0); thus
there's no need to make a difference in sh_eth_tsu_init() between those
controllers. Unfortunately, we can't just remove TSU_QTAG0/1 from the
register *enum* because that would break the ethtool register dump...

Fixes: b0ca2a21 ("sh_eth: Add support of SH7763 to sh_eth")
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>