UBUNTU: [Debian] supply zfs dkms Provides: based on do_zfs

Signed-off-by: Andy Whitcroft <apw@canonical.com>

debian/rules

@@ -88,6 +88,12 @@ binary: binary-indep binary-arch
 
 build: build-arch build-indep
 
+# If we are building zfs update the provides.
+rprovides=
+ifeq ($(do_zfs),true)
+rprovides:=$(rprovides), spl-dkms, zfs-dkms
+endif
+
 clean: debian/control
 	dh_testdir
 	dh_testroot
@@ -144,6 +150,7 @@ $(DEBIAN)/control.stub: $(DEBIAN)/d-i/kernel-versions.in	\
 	        -e 's/ABINUM/$(abinum)/g'                                       \
 		-e 's/SRCPKGNAME/$(src_pkg_name)/g'                             \
 		-e 's/=HUMAN=/$(human_arch)/g'                                    \
+		-e 's/=RPROVIDES=/$(rprovides)/g'                               \
 	  > $$new;								\
 	done
 	flavours="$(sort $(wildcard $(DEBIAN)/control.d/vars.* $(DEBIAN)/sub-flavours/*.vars))";\
@@ -153,6 +160,7 @@ $(DEBIAN)/control.stub: $(DEBIAN)/d-i/kernel-versions.in	\
 		-e 's/ABINUM/$(abinum)/g'                                       \
 		-e 's/SRCPKGNAME/$(src_pkg_name)/g'                             \
 		-e 's/=HUMAN=/$(human_arch)/g'                                    \
+		-e 's/=RPROVIDES=/$(rprovides)/g'                               \
 		>> $(DEBIAN)/control.stub;						\
 	done