ixgbe: fix issues with failing to detect insert of unsupported module

Several small fixes around negative test case of the insertion of a
IXGBE_ERR_NOT_SUPPORTED module.

- mdio45_probe call was always failing due to mdio.prtad not being
set.  The function set to mdio.mdio_read was still working as we just
happen to always be at prtad == 0.  This will allow us to set the phy_id
and phy.type correctly now.

- There was timing issue with i2c calls when initiated from a tasklet.
A small delay was added to allow the electrical oscillation to calm down.

- Logic change in ixgbe_sfp_task that allows NOT_SUPPORTED condition
to be recognized.

Signed-off-by: Don Skidmore <donald.c.skidmore@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ixgbe/ixgbe_phy.c b/drivers/net/ixgbe/ixgbe_phy.c
index 453e966..9ecad17 100644
--- a/drivers/net/ixgbe/ixgbe_phy.c
+++ b/drivers/net/ixgbe/ixgbe_phy.c
@@ -60,6 +60,7 @@
 
 	if (hw->phy.type == ixgbe_phy_unknown) {
 		for (phy_addr = 0; phy_addr < IXGBE_MAX_PHY_ADDR; phy_addr++) {
+			hw->phy.mdio.prtad = phy_addr;
 			if (mdio45_probe(&hw->phy.mdio, phy_addr) == 0) {
 				ixgbe_get_phy_id(hw);
 				hw->phy.type =
@@ -68,6 +69,8 @@
 				break;
 			}
 		}
+		/* clear value if nothing found */
+		hw->phy.mdio.prtad = 0;
 	} else {
 		status = 0;
 	}