nfp: update Agilio SmartNIC flower firmware to rev AOTC-2.9.A.31

This version of the firmware adds support for the offloading of Geneve
tunneling with up to 32 Bytes of options.
Signed-off-by: Louis Peens <louis.peens@netronome.com>
Signed-off-by: Simon Horman <simon.horman@netronome.com>

WHENCE

@@ -3985,7 +3985,7 @@ Link: netronome/flower/nic_AMDA0096-0001_2x10.nffw -> netronome/flower/nic_AMDA0
 Link: netronome/flower/nic_AMDA0097-0001_8x10.nffw -> netronome/flower/nic_AMDA0097.nffw
 Link: netronome/flower/nic_AMDA0099-0001_1x10_1x25.nffw -> netronome/flower/nic_AMDA0099.nffw
 
-Version: AOTC-2.9.A.16
+Version: AOTC-2.9.A.31
 
 Licence: Redistributable. See LICENCE.Netronome for details