fix: label syntax

hosts/swan/disks.nix

@@ -19,7 +19,7 @@
                 type = "filesystem";
                 format = "vfat";
                 mountpoint = "/boot";
-                extraArgs = [ "--label boot" ];
+                extraArgs = [ "-n boot" ];
               };
             }
             {
@@ -33,7 +33,7 @@
                 type = "filesystem";
                 format = "ext4";
                 mountpoint = "/";
-                extraArgs = [ "--label nixos" ];
+                extraArgs = [ "-L nixos" ];
               };
             }
           ];