e1000e: return appropriate errors for 'ethtool -r'

...when invoked while interface is not up or when auto-negotiation is
disabled as done by other drivers.

Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Tested-by: Jeff Pieper <jeffrey.e.pieper@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>