UBUNTU: [Debian] Remove generated intermediate files on clean

BugLink: http://bugs.launchpad.net/bugs/1560445

Remove these files on clean so they do not get included in the
source package.
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

debian/rules

@@ -120,9 +120,12 @@ clean: debian/control
 	# If we have a reconstruct script use it.
 	[ -f $(DEBIAN)/reconstruct ] && bash $(DEBIAN)/reconstruct
 
+	# Remove generated intermediate files
+	rm -f $(DROOT)/control.stub $(DEBIAN)/control.stub \
+		$(DEBIAN)/d-i/kernel-versions
+
 distclean: clean
-	rm -rf $(DROOT)/control $(DROOT)/control.stub $(DEBIAN)/control.stub \
-		$(DEBIAN)/d-i/kernel-versions debian/changelog \
+	rm -rf $(DROOT)/control debian/changelog \
 		debian/control debian/control.stub debian/copyright
 
 # Builds the image, arch headers and debug packages