classes: prepare some classes for native

Enable native recipes to inherit the following classes:
  skeleton-python
  skeleton-sdbus
  skeleton-gdbus
  dbus-dir
  obmc-phosphor-dbus-service

Change-Id: I1d79ffc38792dd48016f09119fc8ace46a304a4b
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/classes/skeleton-sdbus.bbclass b/classes/skeleton-sdbus.bbclass
index 627ce76..d6a1eab 100644
--- a/classes/skeleton-sdbus.bbclass
+++ b/classes/skeleton-sdbus.bbclass
@@ -1,7 +1,11 @@
 inherit skeleton
 
-DEPENDS += "systemd"
+DEPENDS_append_class-target = " systemd"
 
-do_install_append() {
+do_compile_class-native() {
+    :
+}
+
+do_install_append_class-target() {
         oe_runmake install DESTDIR=${D}
 }