isisd: Show correct level information for `show isis interface detail…

… json`

Having this configuration:

```
!
interface r1-eth0
 ip address 10.0.0.1/30
 ip router isis 1
 isis priority 44 level-1
 isis priority 88 level-2
 isis csnp-interval 90 level-1
 isis csnp-interval 99 level-2
 isis psnp-interval 70 level-1
 isis psnp-interval 50 level-2
 isis hello-interval level-1 120
 isis hello-interval level-2 150

!
interface r1-eth1
 ip address 10.0.0.10/30
 ip router isis 1
!
interface lo
 ip address 192.0.2.1/32
 ip router isis 1
 isis passive
!
router isis 1
net 49.0000.0000.0000.0001.00
 metric-style wide
```

Produces:

```
{
 "areas":[
   {
     "area":"1",
     "circuits":[
       {
         "circuit":2,
         "interface":{
           "name":"r1-eth0",
           "state":"Up",
           "is-passive":"active",
           "circuit-id":"0x2",
           "type":"lan",
           "level":"L1L2",
           "snpa":"6e28.9c92.da5e",
           "levels":[
             {
               "level":"L1",
               "metric":10,
               "active-neighbors":1,
               "hello-interval":120,
               "holddown":{
                 "count":10,
                 "pad":"yes"
               },
               "cnsp-interval":90,
               "psnp-interval":70,
               "lan":{
                 "priority":44,
                 "is-dis":"no"
               }
             },
             {
               "level":"L2",
               "metric":10,
               "active-neighbors":1,
               "hello-interval":120, <<<<<<<<<<<<<<<<<<
               "holddown":{
                 "count":10,
                 "pad":"yes"
               },
               "cnsp-interval":90, <<<<<<<<<<<<<<<<<<
               "psnp-interval":70, <<<<<<<<<<<<<<<<<<
               "lan":{
                 "priority":44, <<<<<<<<<<<<<<<<<<
                 "is-dis":"no"
               }
             }
           ],
...
```

Fixes: 9fee4d4 ("isisd: Add json to show isis interface command.")

Signed-off-by: Donatas Abraitis <donatas@opensourcerouting.org>
(cherry picked from commit 360a0d6)

isisd/isis_circuit.c

@@ -1006,45 +1006,40 @@ void isis_circuit_print_json(struct isis_circuit *circuit,
 					       circuit_t2string(level));
 			if (circuit->area->newmetric)
 				json_object_int_add(level_json, "metric",
-						    circuit->te_metric[0]);
+						    circuit->te_metric[level - 1]);
 			else
 				json_object_int_add(level_json, "metric",
-						    circuit->metric[0]);
+						    circuit->metric[level - 1]);
 			if (!circuit->is_passive) {
-				json_object_int_add(level_json,
-						    "active-neighbors",
-						    circuit->upadjcount[0]);
-				json_object_int_add(level_json,
-						    "hello-interval",
-						    circuit->hello_interval[0]);
+				json_object_int_add(level_json, "active-neighbors",
+						    circuit->upadjcount[level - 1]);
+				json_object_int_add(level_json, "hello-interval",
+						    circuit->hello_interval[level - 1]);
 				hold_json = json_object_new_object();
 				json_object_object_add(level_json, "holddown",
 						       hold_json);
-				json_object_int_add(
-					hold_json, "count",
-					circuit->hello_multiplier[0]);
+				json_object_int_add(hold_json, "count",
+						    circuit->hello_multiplier[level - 1]);
 				json_object_string_add(
 					hold_json, "pad",
 					isis_hello_padding2string(
 						circuit->pad_hellos));
 				json_object_int_add(level_json, "cnsp-interval",
-						    circuit->csnp_interval[0]);
+						    circuit->csnp_interval[level - 1]);
 				json_object_int_add(level_json, "psnp-interval",
-						    circuit->psnp_interval[0]);
+						    circuit->psnp_interval[level - 1]);
 				if (circuit->circ_type == CIRCUIT_T_BROADCAST) {
 					lan_prio_json =
 						json_object_new_object();
 					json_object_object_add(level_json,
 							       "lan",
 							       lan_prio_json);
-					json_object_int_add(
-						lan_prio_json, "priority",
-						circuit->priority[0]);
-					json_object_string_add(
-						lan_prio_json, "is-dis",
-						(circuit->u.bc.is_dr[0]
-							 ? "yes"
-							 : "no"));
+					json_object_int_add(lan_prio_json, "priority",
+							    circuit->priority[level - 1]);
+					json_object_string_add(lan_prio_json, "is-dis",
+							       (circuit->u.bc.is_dr[level - 1]
+									? "yes"
+									: "no"));
 				}
 			}
 			json_object_array_add(levels_json, level_json);