LU-4606 utils: Mount uses so for backing fstype

LU-4606 utils: Mount uses so for backing fstype

Make mount/mkfs/tunefs functionality a per backing FSTYPE shared
object that is loadable, and seperately buildable and installable
in the appropriate lustre-osd-FSTYPE rpm.

For ZFS this allows the shared object to be directly linked to libzfs
and thus remove the hardcoding of a libzfs.so version in the lustre
source. This also has the benefit of making lustre-osd-zfs explicitly
requires libzfs (which it needs to do mount/mkfs operations).

Adjust build system to allow building of loadable module.  Including
requiering libtool as part of the build.

Lustre-change: http://review.whamcloud.com/10193
Lustre-commit: 3e8c354c09725a97b90e477a77411cc6fb306f09

LU-5091 build: Support alternate locations of libzfs.so

Due to the change for with-zfs-devel (LU-3497), also add support to
search for libzfs.so along with the alternate locations supplied with
the header files.
Also need to unpack zfs{,-devel}.  The zfs RPM is needed because it
has the actual libraries in it and the zfs-devel RPM only has un-
versioned symlinks to the libraries in the zfs RPM.
This will all change one day when we have a libzfs RPM per
https://github.com/zfsonlinux/zfs/issues/2329 and it looks like it
could be one day soon: https://github.com/zfsonlinux/zfs/pull/2341.

Lustre-change: http://review.whamcloud.com/10401
Lustre-commit: b2659030edb7d34c91430ff924bab23881b6c230

Signed-off-by: Nathaniel Clark <nathaniel.l.clark@intel.com>
Signed-off-by: Brian J. Murrell <brian.murrell@intel.com>
Reviewed-by: James Simmons <uja.ornl@gmail.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Change-Id: I1d69b64eec1589f63e24f20cc624778a4be2ec60
Reviewed-on: http://review.whamcloud.com/11297
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>