staging/lustre: remove INIT_CTL_NAME

legacy code used to support kernel where struct ctl_table
has ctl_name member.

Cc: Andreas Dilger <andreas.dilger@intel.com>
Signed-off-by: Peng Tao <bergwolf@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>