Merge pull request #97505 from mayflower/grub-efi-mirroredboot

nixos/grub: allow multiple "nodev" devices for mirroredBoots

nixos/modules/system/boot/loader/grub/grub.nix

···
             + "'boot.loader.grub.mirroredBoots' to make the system bootable.";
         }
         {
-          assertion = cfg.efiSupport || all (c: c < 2) (mapAttrsToList (_: c: c) bootDeviceCounters);
+          assertion = cfg.efiSupport || all (c: c < 2) (mapAttrsToList (n: c: if n == "nodev" then 0 else c) bootDeviceCounters);
           message = "You cannot have duplicated devices in mirroredBoots";
         }
         {