This patch adds support for receiving interrupts from a external copper
PHY for the X550 part.  This includes enabling, detection as well as
re-enablement.
Signed-off-by: NDon Skidmore <donald.c.skidmore@intel.com>
Tested-by: NKrishneil Singh <krishneil.k.singh@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>