Fix dns_read_zone_view() not returning global variables properly

lib/dns.sh

@@ -530,16 +530,13 @@ dns_select_record_type() {
 dns_read_zone_view() {
   local zone_retvar=$1
   local view_retvar=$2
-  
-  local zone view 
+
+  local zone view
   while [ -z "$zone" ]; do
     read -e -p "Zone name (ZONE or ZONE@VIEW): " zone
-    [ -n "$zone" ] && ! dns_check_zone_name_view "$zone" zone view && zone=""
+    [ -n "$zone" ] && ! dns_check_zone_name_view "$zone" "$zone_retvar" "$view_retvar" && zone=""
   done
   echo
-
-  declare -g $zone_retvar="$zone"
-  declare -g $view_retvar="$view"
 }
 
 dns_read_record_name() {