net: lan78xx: Drop unnecessary strcpy in lan78xx_probe

There is no need for this strcpy because alloc_etherdev() already
does this job.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Raghuram Chary Jallipalli <raghuramchary.jallipalli@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>