declare AFFS, CPIO, TAR and XFS as non-installable explicitly

grub-core/fs/affs.c

@@ -535,6 +535,9 @@ static struct grub_fs grub_affs_fs =
     .read = grub_affs_read,
     .close = grub_affs_close,
     .label = grub_affs_label,
+#ifdef GRUB_UTIL
+    .reserved_first_sector = 0,
+#endif
     .next = 0
   };
 

grub-core/fs/cpio.c

@@ -362,6 +362,9 @@ static struct grub_fs grub_cpio_fs = {
   .open = grub_cpio_open,
   .read = grub_cpio_read,
   .close = grub_cpio_close,
+#ifdef GRUB_UTIL
+  .reserved_first_sector = 0,
+#endif
 };
 
 #ifdef MODE_USTAR

grub-core/fs/xfs.c

@@ -822,6 +822,9 @@ static struct grub_fs grub_xfs_fs =
     .close = grub_xfs_close,
     .label = grub_xfs_label,
     .uuid = grub_xfs_uuid,
+#ifdef GRUB_UTIL
+    .reserved_first_sector = 0,
+#endif
     .next = 0
   };