staging: hv: Fix missing functions for net_device_ops

staging: hv: Fix missing functions for net_device_ops

commit b681b5886bb5d1f5b6750a0ed7c62846da7ccea4 upstream.

Fix missing functions for net_device_ops.
It's a bug when porting the drivers from 2.6.27 to 2.6.32. In 2.6.27,
the default functions for Ethernet, like eth_change_mtu(), were assigned
by ether_setup(). But in 2.6.32, these function pointers moved to
net_device_ops structure and no longer be assigned in ether_setup(). So
we need to set these functions in our driver code. It will ensure the
MTU won't be set beyond 1500. Otherwise, this can cause an error on the
server side, because the HyperV linux driver doesn't support jumbo frame
yet.

Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Hank Janssen <hjanssen@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>