amd-xgbe: fix the false linkup in xgbe_phy_status

In the event of a change in XGBE mode, the current auto-negotiation
needs to be reset and the AN cycle needs to be re-triggerred. However,
the current code ignores the return value of xgbe_set_mode(), leading to
false information as the link is declared without checking the status
register.

Fix this by propagating the mode switch status information to
xgbe_phy_status().

Fixes: e57f7a3f

 ("amd-xgbe: Prepare for working with more than one type of phy")
Co-developed-by: Sudheesh Mavila <sudheesh.mavila@amd.com>
Signed-off-by: Sudheesh Mavila <sudheesh.mavila@amd.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Acked-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
Signed-off-by: Raju Rangoju <Raju.Rangoju@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>