ixgbe: remove global reset to the MAC

Reloading FW during resets can cause issues. Remove the full reset
as it is not needed.

Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>