staging:lustre: Delete all obsolete LND drivers

staging:lustre: Delete all obsolete LND drivers

Remove ralnd, ptllnd, mxlnd, qswlnd drivers. They are no
longer supported and have not even been buildable
for a long time.

Signed-off-by: James Simmons <uja.ornl@gmail.com>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-6209
Reviewed-on: http://review.whamcloud.com/13663
Reviewed-by: Isaac Huang <he.huang@intel.com>
Reviewed-by: Doug Oucharek <doug.s.oucharek@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>