[VOL-5358] - build & test repo using new AMI image

makefiles/etc/features.mk
makefiles/etc/include.mk
makefiles/include.mk
-------------------------
  o Wrap features.mk with a include-once guard macro.
  o Dependency-less macros like banner, banner-enter, etc need to be
    included early so makefiles beneath lf/local/ can make use of them.

Change-Id: I54c19e1dbf4bded41fa4976a2241bdeb0ed06903
diff --git a/makefiles/include.mk b/makefiles/include.mk
index ee2792d..0884be3 100644
--- a/makefiles/include.mk
+++ b/makefiles/include.mk
@@ -50,10 +50,16 @@
 
 ONF_MAKEDIR   := $(onf-mk-dir)#   # TODO: Deprecate ONF_MAKEDIR and MAKEDIR
 
+##-------------------------##
+##---]  CORE INCLUDES  [---##
+##-------------------------##
+# no external dependencies.
+# wrap with a guard macro (include-once) to prevent re-sourcing.
+$(call include-once,$(onf-mk-dir)/etc/features.mk)
+
 ##--------------------##
 ##---]  INCLUDES  [---##
 ##--------------------##
-
 include $(onf-mk-dir)/detect/include.mk     # Dynamic features based on source
 
 include $(onf-mk-dir)/lint/make/warn-undef-vars.mk  # target lint-make helper