net: macb: Adding Support for Jumbo Frames up to 10240 Bytes in SAMA5D3

net: macb: Adding Support for Jumbo Frames up to 10240 Bytes in SAMA5D3

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>