be2net: re-order fields in be_error_recovert to avoid hole

- Unionize two u8 fields where only one of them is used depending on NIC
chipset.
- Move recovery_supported field after that union

These changes eliminate 7-bytes hole in the struct and makes it smaller
by 8 bytes.

Signed-off-by: Ivan Vecera <cera@cera.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>