FITS: generating send-streams in portable format
This commit adds the command 'zfs fits-send', analogous to zfs send. The
generated send stream is compatible with the stream generated with that
from 'btrfs send' and can in principle easily be received to any filesystem.

@@ -823,10 +823,11 @@
         ZFS_IOC_SEND_PROGRESS,
         ZFS_IOC_LOG_HISTORY,
         ZFS_IOC_SEND_NEW,
         ZFS_IOC_SEND_SPACE,
         ZFS_IOC_CLONE,
+        ZFS_IOC_FITS_SEND,
         ZFS_IOC_LAST
 } zfs_ioc_t;
 
 /*
  * Internal SPA load state.  Used by FMA diagnosis engine.