zebra: json support for show ip nht route-map

zebra: json support for show ip nht route-map

Changes:
JSON support added for below commands,
     - show ip nht route-map vrf all json
     - show ip nht route-map vrf <name> json
     - show ipv6 nht route-map vrf all json
     - show ipv6 nht route-map vrf <name> json
     - show ipv6 nht route-map json
     - show ip nht route-map json

Testing Done: Unit testing completed.

tor-1# show ip nht route-map vrf default json
{
  "afi":"ipv4",
  "vrfs":{
	"default":{
	  "protocols":{
		"system":"none",
		"kernel":"none",
		"connected":"connected-policy",
		"static":"none",
		"rip":"none",
		"ripng":"none",
		"ospf":"none",
		"ospf6":"none",
		"isis":"none",
		"bgp":"bgp-policy",
		"pim":"none",
		"eigrp":"none",
		"nhrp":"none",
		"hsls":"none",
		"olsr":"none",
		"table":"none",
		"ldp":"none",
		"vnc":"none",
		"vnc-direct":"none",
		"vnc-rn":"none",
		"bgp-direct":"none",
		"bgp-direct-to-nve-groups":"none",
		"babel":"none",
		"sharp":"none",
		"pbr":"none",
		"bfd":"none",
		"openfabric":"none",
		"vrrp":"none",
		"zebra":"none",
		"frr":"none",
		"wildcard":"none",
		"any":"none"
	  }
	}
  }
}

tor-1# show ip nht route-map vrf all json
{
  "afi":"ipv4",
  "vrfs":{
	"default":{
	  "protocols":{
		"system":"none",
		"kernel":"none",
		"connected":"connected-policy",
		"static":"none",
		"rip":"none",
		"ripng":"none",
		"ospf":"none",
		"ospf6":"none",
		"isis":"none",
		"bgp":"bgp-policy",
		"pim":"none",
		"eigrp":"none",
		"nhrp":"none",
		"hsls":"none",
		"olsr":"none",
		"table":"none",
		"ldp":"none",
		"vnc":"none",
		"vnc-direct":"none",
		"vnc-rn":"none",
		"bgp-direct":"none",
		"bgp-direct-to-nve-groups":"none",
		"babel":"none",
		"sharp":"none",
		"pbr":"none",
		"bfd":"none",
		"openfabric":"none",
		"vrrp":"none",
		"zebra":"none",
		"frr":"none",
		"wildcard":"none",
		"any":"none"
	  }
	},
	"mgmt":{
	  "protocols":{
		"system":"none",
		"kernel":"none",
		"connected":"none",
		"static":"none",
		"rip":"none",
		"ripng":"none",
		"ospf":"none",
		"ospf6":"none",
		"isis":"none",
		"bgp":"none",
		"pim":"none",
		"eigrp":"none",
		"nhrp":"none",
		"hsls":"none",
		"olsr":"none",
		"table":"none",
		"ldp":"none",
		"vnc":"none",
		"vnc-direct":"none",
		"vnc-rn":"none",
		"bgp-direct":"none",
		"bgp-direct-to-nve-groups":"none",
		"babel":"none",
		"sharp":"none",
		"pbr":"none",
		"bfd":"none",
		"openfabric":"none",
		"vrrp":"none",
		"zebra":"none",
		"frr":"none",
		"wildcard":"none",
		"any":"none"
	  }
	},
	"sym_1":{
	  "protocols":{
		"system":"none",
		"kernel":"none",
		"connected":"none",
		"static":"none",
		"rip":"none",
		"ripng":"none",
		"ospf":"none",
		"ospf6":"none",
		"isis":"none",
		"bgp":"bgp-policy",
		"pim":"none",
		"eigrp":"none",
		"nhrp":"none",
		"hsls":"none",
		"olsr":"none",
		"table":"none",
		"ldp":"none",
		"vnc":"none",
		"vnc-direct":"none",
		"vnc-rn":"none",
		"bgp-direct":"none",
		"bgp-direct-to-nve-groups":"none",
		"babel":"none",
		"sharp":"none",
		"pbr":"none",
		"bfd":"none",
		"openfabric":"none",
		"vrrp":"none",
		"zebra":"none",
		"frr":"none",
		"wildcard":"none",
		"any":"none"
	  }
	}
  }
}

tor-1# show ipv6 nht route-map vrf default json
{
  "afi":"ipv6",
  "vrfs":{
	"default":{
	  "protocols":{
		"system":"none",
		"kernel":"kernel-policy",
		"connected":"connected-policy",
		"static":"none",
		"rip":"none",
		"ripng":"none",
		"ospf":"none",
		"ospf6":"none",
		"isis":"none",
		"bgp":"none",
		"pim":"none",
		"eigrp":"none",
		"nhrp":"none",
		"hsls":"none",
		"olsr":"none",
		"table":"none",
		"ldp":"none",
		"vnc":"none",
		"vnc-direct":"none",
		"vnc-rn":"none",
		"bgp-direct":"none",
		"bgp-direct-to-nve-groups":"none",
		"babel":"none",
		"sharp":"none",
		"pbr":"none",
		"bfd":"none",
		"openfabric":"none",
		"vrrp":"none",
		"zebra":"none",
		"frr":"none",
		"wildcard":"none",
		"any":"none"
	  }
	}
  }
}

Ticket:#3229016
Issue:3229016

Signed-off-by: Sindhu Parvathi Gopinathan <sgopinathan@nvidia.com>