ixgbe: fix response to apply-update command

For the "Apply Update" command the firmware does not
given an response. For this command, success should
be return.

Signed-off-by: Mateusz Kowalski <mateusz.kowalski@intel.com>
Signed-off-by: Guinan Sun <guinanx.sun@intel.com>
Reviewed-by: Wei Zhao <wei.zhao1@intel.com>

Approved by: imp
Obtained from: DPDK (03b09c71c0c6c516ce05cad8e8aa75e8b9e14fba)
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D31621

(cherry picked from commit c966c431c764c493fafbe65b717243a3c0b291be)