hook up ZFS Makefiles into Dfly Makefile system

Signed-off-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
cddl/*/Makefile: Deal with src.opts.mk

In DragonflyBSD we don't have 'src.opts.mk' for MK_FOO like FreeBSD
has. Trim that out of the Makefiles with tests and dtrace bits.

Signed-off-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
cddl/*/Makefile: Change MK_FOO -> NO_FOO

Signed-off-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
sys/cddl/compat/opensolaris: Dfly supports DIOCGPART for ioctl

Signed-off-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
sys/sys/sdt.h: Missing header in ZFS port

Probably can prune this latter.

Signed-off-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
cddl/lib/Makefile: libctf not yet

Don't build libctf just yet..

Signed-off-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>