staging: hv: Enable sending GARP packet after live migration

The hv_netvsc gets RNDIS_STATUS_MEDIA_CONNECT event after the VM
is live migrated. Adding call to netif_notify_peers() for this event
to send GARP (Gratuitous ARP) to notify network peers. Otherwise,
the VM's network connection may stop after a live migration.

This patch should also be applied to stable kernel 2.6.32 and later.

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