nixos/swap: add options option

nixos/modules/config/swap.nix

@@ -127,6 +127,15 @@ let
         '';
       };
 
+      options = mkOption {
+        default = [ "defaults" ];
+        example = [ "nofail" ];
+        type = types.listOf types.nonEmptyStr;
+        description = ''
+          Options used to mount the swap.
+        '';
+      };
+
       deviceName = mkOption {
         type = types.str;
         internal = true;

nixos/modules/tasks/filesystems.nix

@@ -255,7 +255,7 @@ in
         # https://wiki.archlinux.org/index.php/fstab#Filepath_spaces
         escape = string: builtins.replaceStrings [ " " "\t" ] [ "\\040" "\\011" ] string;
         swapOptions = sw: concatStringsSep "," (
-          [ "defaults" ]
+          sw.options
           ++ optional (sw.priority != null) "pri=${toString sw.priority}"
           ++ optional (sw.discardPolicy != null) "discard${optionalString (sw.discardPolicy != "both") "=${toString sw.discardPolicy}"}"
         );