LU-5814 lov: move LSM to LOV layer

LU-5814 lov: move LSM to LOV layer

Move the definition of struct lov_stripe_md along with supporting
functions from obd.h to lov_internal.h. Remove the unused functions
obd_packmd() and obd_free_diskmd(). Simplify lov_obd_packmd()
according to the reduced use cases and rename it lov_packmd().

Signed-off-by: John L. Hammond <john.hammond@intel.com>
Change-Id: I873a08f20bcb2e0919695325e51d74b2b97f4f0c
Signed-off-by: Jinshan Xiong <jinshan.xiong@intel.com>
Reviewed-on: http://review.whamcloud.com/13696
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>