staging/lustre: Remove ldlm type/mode typedefs

Replace ldlm_mode_t with enum ldlm_mode,
ldlm_type_t with enum ldlm_type

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