Hardware NAT For LEDE

@gwlim I ran some Archer C7 tests too. It looks like HW NAT is active and makes a difference, but right now I'm seeing a performance degradation. [tests removed because the degraded performance was caused by other factors]

NAT with other firmware - 484mb/s
NAT on the April NAT build - 395mb/s - with a lot of jitter in the speed

Direct switch connection - 891mb/s - probably not relevant but doing the extra test was easy

C7 Direct Switch-Switch

PS C:\Users\denis\Desktop\iperf-3.1.3-win64> .\iperf3.exe iperf -c 10.5.1.15
Connecting to host 10.5.1.15, port 5201
[  4] local 10.5.1.184 port 51425 connected to 10.5.1.15 port 5201
[ ID] Interval           Transfer     Bandwidth
[  4]   0.00-1.00   sec   106 MBytes   889 Mbits/sec
[  4]   1.00-2.00   sec   105 MBytes   882 Mbits/sec
[  4]   2.00-3.00   sec   106 MBytes   892 Mbits/sec
[  4]   3.00-4.00   sec   106 MBytes   893 Mbits/sec
[  4]   4.00-5.00   sec   106 MBytes   893 Mbits/sec
[  4]   5.00-6.00   sec   106 MBytes   892 Mbits/sec
[  4]   6.00-7.00   sec   106 MBytes   892 Mbits/sec
[  4]   7.00-8.00   sec   106 MBytes   893 Mbits/sec
[  4]   8.00-9.00   sec   106 MBytes   891 Mbits/sec
[  4]   9.00-10.00  sec   106 MBytes   891 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth
[  4]   0.00-10.00  sec  1.04 GBytes   891 Mbits/sec                  sender
[  4]   0.00-10.00  sec  1.04 GBytes   891 Mbits/sec                  receiver

C7 Without Hardware NAT

PS C:\Users\denis\Desktop\iperf-3.1.3-win64> .\iperf3.exe iperf -c 10.5.1.15
Connecting to host 10.5.1.15, port 5201
[  4] local 192.168.1.184 port 50634 connected to 10.5.1.15 port 5201
[ ID] Interval           Transfer     Bandwidth
[  4]   0.00-1.00   sec  59.8 MBytes   501 Mbits/sec
[  4]   1.00-2.00   sec  58.5 MBytes   491 Mbits/sec
[  4]   2.00-3.00   sec  59.5 MBytes   499 Mbits/sec
[  4]   3.00-4.00   sec  57.4 MBytes   481 Mbits/sec
[  4]   4.00-5.00   sec  59.6 MBytes   500 Mbits/sec
[  4]   5.00-6.00   sec  58.2 MBytes   489 Mbits/sec
[  4]   6.00-7.00   sec  49.4 MBytes   414 Mbits/sec
[  4]   7.00-8.00   sec  57.1 MBytes   479 Mbits/sec
[  4]   8.00-9.00   sec  59.4 MBytes   499 Mbits/sec
[  4]   9.00-10.00  sec  58.2 MBytes   489 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth
[  4]   0.00-10.00  sec   577 MBytes   484 Mbits/sec                  sender
[  4]   0.00-10.00  sec   577 MBytes   484 Mbits/sec                  receiver

C7 With Hardware NAT

<this test has been removed because I didn't account for other traffic on the network and it was innacurate>