LU-7669 lmv: assume a real connection in lmv_connect()

LU-7669 lmv: assume a real connection in lmv_connect()

Assume a real connection in lmv_connect(). Mark OBD_CONNECT_REAL
obsolete. Remove the then unnecessary refcount and exp members of
struct lmv_obd. Remove calls to lmv_check_connect(). Disconnect the
export in the appropriate error path of lmv_connect().

Signed-off-by: John L. Hammond <john.hammond@intel.com>
Change-Id: I6d4f449506020964afd7f012983bfb2339429e0f
Reviewed-on: http://review.whamcloud.com/18018
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: wangdi <di.wang@intel.com>