MFV r323911:

MFV r323911:
8502 illumos#7955 broke delegated datasets when libshare is not present

illumos/illumos-gate@1c18e8fbd8db41a9fb39bd3ef7a18ee71ece20da
https://github.com/illumos/illumos-gate/commit/1c18e8fbd8db41a9fb39bd3ef7a18ee71ece20da

https://www.illumos.org/issues/8502
  The code in lib/libzfs/common/libzfs_mount.c already basically handles
  the case when libshare is not installed. We just need to not fail in
  zfs_init_libshare_impl.  I tested this in lx and things work as
  expected. I also tested there trying to set sharenfs and sharesmb on
  the delegated dataset. Neither is allowed from within a zone.  The
  spew of msgs from a native zone is not ZFS specific. I see the same
  spew simply running the share command.

Reviewed by: Robert Mustacchi <rm@joyent.com>
Reviewed by: Yuri Pankov <yuripv@gmx.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
Author: Jerry Jelinek <jerry.jelinek@joyent.com>