[VOL-5064] - Build and deploy voltha-system-tests

makefiles/
----------
  o Copy in latest library makefiles from repo:onf-make

config.mk
makefiles/lint
--------------
  o Support more lint targets

makefiles/virtualenv.mk
-----------------------
  o Update to use library logic.
  o Install/maintain .venv/ VS vst_venv.
  o Proper dependency driven create when needed VS always install.
  o Also support replacing inlined venv logic with library makefile logs.

makefiles/commands/kail.mk
--------------------------
  o mkdir -p for interactive use when WORKSPACE= is set.

Makefile
--------
  o Inline comment delimiters and help targets to improve readabilty.
  o Call macro banner-enter/banner-leave to hilight target output.
  o Change targets clean and help into double-colon rules so they
    are included when library targets are processed.
  o Update include $(MAKEDIR) imports, library makefiles are able to infer paths
    and define MAKDIR=, ONF_MAKEDIR=.
  o Define helper macro run-robot-test= allowing copy & paste robot command
    line to be refactored and reduced.
  o Define local target 'venv-install' allowing installation of the virtualenv
    followed by patching so a newer interpreter can be used locally for testing.
  o Shell command separator: replace ';' with '&&' to improve error detection.
  o target=gendocs: Split run-on command line into independent steps, activate
    script only applies to the for loop invoking tests.

Change-Id: Idc8efd89f36b9f4954d9394a6524e07aa2ea5531
diff --git a/makefiles/jjb/required.mk b/makefiles/jjb/required.mk
new file mode 100644
index 0000000..17371e9
--- /dev/null
+++ b/makefiles/jjb/required.mk
@@ -0,0 +1,33 @@
+# -*- makefile -*-
+# -----------------------------------------------------------------------
+# Copyright 2022-2023 Open Networking Foundation (ONF) and the ONF Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# -----------------------------------------------------------------------
+# Intent: Conditionally load when named targets are requested.
+#   var ?= $(error ...) definitions are fatal to "make help" and others
+# -----------------------------------------------------------------------
+
+onf-mk-jjb-targets := $(NULL)
+onf-mk-jjb-targets += jjb-gen
+onf-mk-jjb-targets += sterile
+
+# -----------------------------------------------------------------------
+# Define a flag to only load release targets when mentioned by name
+# Makefile can also explicitly define the flag to force always loading.
+# -----------------------------------------------------------------------
+$(foreach tgt,$(onf-mk-jjb-targets),\
+  $(if $(findstring $(tgt),$(MAKECMDGOALS)),$(eval USE-ONF-JJB-MK := true))\
+)
+
+# [EOF]