bgpd: fix advertisedRoutes json key

bgpd: fix advertisedRoutes json key

'show bgp ... neighbor [routes|received-routes]' both incorrectly
used a json key of 'advertisedRoutes'.
This corrects the key to be 'receivedRoutes' for commands where
the displayed routes were received, not advertised.

before:
unet> r3 show ip bgp neigh 10.2.30.2 received-routes json | include Routes
  "advertisedRoutes":{

after:
ub18# show ip bgp neighbors enp1s0 received-routes json | include Routes
  "receivedRoutes":{
ub18# show ip bgp neighbors enp1s0 advertised-routes json | include Routes
  "advertisedRoutes":{

Signed-off-by: Trey Aspelund <taspelund@nvidia.com>