net: sh_eth: Correct fix for RX packet errors on R8A7740

Nguyen Hong Ky posted a patch to correct RX packet errors on R8A7740 which
was applied as 2c6221e4 ("net: sh_eth: Fix RX packets errors on
R8A7740"). Unfortunately sh_eth.c contains many similar instances
of struct sh_eth_cpu_data and the patch was miss-applied, updating
sh7734_data instead of r8a7740_data.

This patch corrects this problem by.
1. Reverting the change to sh7734_data and;
2. Applying the change to r8a7740_data.

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>