dlm: linux/{dlm,dlm_device}.h: cleanup for userspace

linux/dlm_device.h uses types from dlm.h and types.h, so pull them in.  The
dlm.h header should use __u## rather than uint##_t types and thus pull in
linux/types.h for it.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: David Teigland <teigland@redhat.com>