sfc: add ndo_set_vf_link_state() function for EF10

Exercised with
"ip link set <PF intf> vf <vf_i> state {auto|enable|disable}"
Sets the reporting policy for VF link state to either
 - mirror physical link state
 - always up
 - always down

get VF link state mode in efx_ef10_sriov_get_vf_config

Exercised by
"ip link show <PF intf>";
output will include a line like
vf 0 MAC 12:34:56:78:9a:bc, link-state auto

Signed-off-by: Shradha Shah <sshah@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/sfc/net_driver.h b/drivers/net/ethernet/sfc/net_driver.h
index 364217b..c2eabd9 100644
--- a/drivers/net/ethernet/sfc/net_driver.h
+++ b/drivers/net/ethernet/sfc/net_driver.h
@@ -1348,6 +1348,8 @@
 				     bool spoofchk);
 	int (*sriov_get_vf_config)(struct efx_nic *efx, int vf_i,
 				   struct ifla_vf_info *ivi);
+	int (*sriov_set_vf_link_state)(struct efx_nic *efx, int vf_i,
+				       int link_state);
 	int (*vswitching_probe)(struct efx_nic *efx);
 	int (*vswitching_restore)(struct efx_nic *efx);
 	void (*vswitching_remove)(struct efx_nic *efx);