i40e: For VF reset (VFR and VFLR) add some more delay

With a HW issue that was recently discovered, after a VFLR HW might be
indicating to us a reset completion little too early. So wait another 10
msec for cache to be cleaned up.

Change-ID: I6a24dcf5dd7ffcd6500246e717411ef58532d1e9
Signed-off-by: NAnjali Singhai Jain <anjali.singhai@intel.com>
Tested-by: NJim Young <james.m.young@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c

@@ -812,6 +812,9 @@ void i40e_reset_vf(struct i40e_vf *vf, bool flr)
 		}
 	}
 
+	if (flr)
+		usleep_range(10000, 20000);
+
 	if (!rsd)
 		dev_err(&pf->pdev->dev, "VF reset check timeout on VF %d\n",
 			vf->vf_id);