3966 zfs lz4 compression (etc) should have bumped grub capability VERSION

@@ -958,10 +958,13 @@
 
 /*
  * List of pool features that the grub implementation of ZFS supports for
  * read. Note that features that are only required for write do not need
  * to be listed here since grub opens pools in read-only mode.
+ *
+ * When this list is updated the version number in usr/src/grub/capability
+ * must be incremented to ensure the new grub gets installed.
  */
 static const char *spa_feature_names[] = {
         "org.illumos:lz4_compress",
         NULL
 };