As per the SAMA5D3 device specification it supports Jumbo frames.
But the suggested flag and length of bytes it supports was not updated
in this driver config_structure.
The maximum jumbo frames the device supports :
10240 bytes as per the device spec.

While changing the MTU value greater than 1500, it threw error:
sudo ifconfig eth1 mtu 9000
SIOCSIFMTU: Invalid argument

Add this support to driver so that it works as expected and designed.
Signed-off-by: vishnuvardhan <vardhanraj4143@gmail.com>
[nicolas.ferre@microchip.com: modify slightly commit msg]
Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>