Allow access to the Sidecar SP in unlocked Reverso state

[mkeeter]

Previously, unlocking the management network on a reverso image would give access to the Scrimlet SP, but would disable access to the Sidecar SP.

matt@niles ~ () $ pilot sp ls
MAC               SERIAL      TYPE    IMAGE            IP
a8:40:25:05:ff:00 BRM44220001 sidecar 8ce4ec6791c36fbe fe80::aa40:25ff:fe05:ff00
matt@niles ~ () $ faux-mgs --discovery-addr='[fe80::aa40:25ff:fe05:ff00]:11111' --interface=axf6 monorail unlock -t1h
Mar 11 17:45:42.765 INFO creating SP handle on interface axf6, component: faux-mgs
Mar 11 17:45:42.767 INFO initial discovery complete, addr: [fe80::aa40:25ff:fe05:ff00%4]:11111, interface: axf6, socket: control-plane-agent, component: faux-mgs
Mar 11 17:45:42.794 INFO received challenge Trivial { timestamp: 105789 }, component: faux-mgs
Error: RPC call failed (gave up after 5 attempts)
matt@niles ~ () $ pilot sp ls
MAC               SERIAL      TYPE    IMAGE            IP
a8:40:25:04:07:47 BRM27230059 gimlet  99b02be7e74ee625 fe80::aa40:25ff:fe04:747
# ...where Sidecar?

This PR fixes the issue:

matt@niles ~ () $ pilot sp ls
MAC               SERIAL      TYPE    IMAGE            IP
a8:40:25:05:ff:00 BRM44220001 sidecar 6f0040f71ea5bc66 fe80::aa40:25ff:fe05:ff00
matt@niles ~ () $ faux-mgs --discovery-addr='[fe80::aa40:25ff:fe05:ff00]:11111' --interface=axf6 monorail unlock -t1h
Mar 11 17:51:18.562 INFO creating SP handle on interface axf6, component: faux-mgs
Mar 11 17:51:18.564 INFO initial discovery complete, addr: [fe80::aa40:25ff:fe05:ff00%4]:11111, interface: axf6, socket: control-plane-agent, component: faux-mgs
Mar 11 17:51:18.591 INFO received challenge Trivial { timestamp: 27171 }, component: faux-mgs
done
matt@niles ~ () $ pilot sp ls
MAC               SERIAL      TYPE    IMAGE            IP
a8:40:25:04:07:47 BRM27230059 gimlet  99b02be7e74ee625 fe80::aa40:25ff:fe04:747
a8:40:25:05:ff:00 BRM44220001 sidecar 6f0040f71ea5bc66 fe80::aa40:25ff:fe05:ff00