net: thunderx: Enable BGX LMAC's RX/TX only after VF is up

Enable or disable BGX LMAC's RX/TX based on corresponding VF's
status. If otherwise, when multiple LMAC's physical link is up
then packets from all LMAC's whose corresponding VF is not yet
initialized will get forwarded to VF0. This is due to VNIC's default
configuration where CPI, RSSI e.t.c point to VF0/QSET0/RQ0.

This patch will prevent multiple copies of packets on VF0.

Signed-off-by: Sunil Goutham <sgoutham@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>