meas_json: fix NEIGH: missing array braces

Make NEIGH an array of Javascript objects, otherwise the JSON is not parseable
when neighbours exist

Change-Id: I42029f40bf357adbb2f3c71cdcbafbc21090e348
diff --git a/openbsc/src/utils/meas_json.c b/openbsc/src/utils/meas_json.c
index 93203bc..51eb6c7 100644
--- a/openbsc/src/utils/meas_json.c
+++ b/openbsc/src/utils/meas_json.c
@@ -89,7 +89,7 @@
 	for (i = 0; i < mr->num_cell; i++) {
 		struct gsm_meas_rep_cell *mrc = &mr->cell[i];
 		if (i!=0) printf(", ");
-		printf("\"IDX\":%u, \"ARFCN\":%u, \"BSIC\":%u, \"POWER\":%d",
+		printf("{\"IDX\":%u, \"ARFCN\":%u, \"BSIC\":%u, \"POWER\":%d}",
 			mrc->neigh_idx, mrc->arfcn, mrc->bsic, rxlev2dbm(mrc->rxlev));
 	}
 	printf("]");
@@ -151,6 +151,7 @@
 	default:
 		break;
 	}
+	return 0;
 }
 
 static int udp_fd_cb(struct osmo_fd *ofd, unsigned int what)