staging/lustre/ldlm: Preparation to move /proc/fs/lustre/ldlm to sysfs

Add necessary infrastructure, register /sys/fs/lustre/ldlm,
/sys/fs/lustre/ldlm/namespaces and /sys/fs/lustre/ldlm/services

Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>