[VOL-5051] - Triage bbsim build

[VOL-5092] - verify_bbsim_unit-test repository failures in jenkins job history.

makefiles/*
-----------
  o Merge in latest library makefiles.
  o Some legacy retained:
      tools.mk => makefiles/docker/include.mk
      makefiles/lint/docker/*.mk (replace with docker/include.mk.new)

Makefile
--------
  o Remove bogus foobar target.
  o Target docs-lint now maps to library target lint-doc8.

docs/Makefile
-------------
  o venv install now handled by makefiles/virtualenv.mk
  o Replaced inlined doc8 lint target with makefiles/lint/doc8 (lint-doc8)
  o Use std defines for SHELL= and other constants.
  o Replace separator ';' with '&&' in commands using venv (detect errors).

config.mk
---------
  o Enable lint targets for doc8, docker & json.
  o More lint checks can be enabled but cleanup is needed first.

docs/Makefile
requirements.txt
----------------
  o Identified a few python module problems documented in VOL-5092.
  o Makefile wild target(%) matching stray dependencies so hardcode sphinx targets to act on.
  o Added hyphen/success to "make docs" until VOL-5092 can be straightened out.

Change-Id: Ibe4006747ee610bfe8ac0fdbb339e5e18e6e9176
diff --git a/docs/Makefile b/docs/Makefile
index a2df413..255abff 100644
--- a/docs/Makefile
+++ b/docs/Makefile
@@ -1,7 +1,39 @@
-# Minimal makefile for Sphinx documentation
+# -*- makefile -*-
+# -----------------------------------------------------------------------
+# Copyright 2017-2023 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.
+# -----------------------------------------------------------------------
 
-# use bash safe mode, fail quickly
-SHELL = bash -e -o pipefail
+$(if $(DEBUG),$(warning ENTER))
+
+##-------------------##
+##---]  GLOBALS  [---##
+##-------------------##
+TOP-docs ?=$(strip \
+  $(dir \
+    $(abspath $(lastword $(MAKEFILE_LIST)))\
+   )\
+)
+TOP-docs := $(subst /docs/,$(null),$(TOP-docs))
+
+##--------------------##
+##---]  INCLUDES  [---##
+##--------------------##
+include $(TOP-docs)/config.mk
+include $(TOP-docs)/makefiles/include.mk
+
+# Minimal makefile for Sphinx documentation
 
 # You can set these variables from the command line.
 SPHINXOPTS    =
@@ -11,29 +43,28 @@
 
 .PHONY: help Makefile lint
 
-# Put it first so that "make" without argument is like "make help".
-help: doc_venv
-	source $</bin/activate ; set -u ;\
-	$(SPHINXBUILD) -M help "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
+## -----------------------------------------------------------------------
+## -----------------------------------------------------------------------
+clean ::
+	$(RM) -r build "$(venv-name)"
 
-doc_venv:
-	virtualenv -p python3 $@ ;\
-	source $@/bin/activate ;\
-	pip install -r requirements.txt
+## -----------------------------------------------------------------------
+## Intent: Display target help
+## -----------------------------------------------------------------------
+help :: $(venv-activate-script)
+	$(activate) \
+	  && $(SPHINXBUILD) -M help "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
 
-lint: doc8
-
-doc8: doc_venv
-	source $</bin/activate ; set -u ;\
-	doc8 --max-line-length 119 \
-	     $$(find . -name \*.rst ! -path "*doc_venv*")
-
-clean:
-	rm -rf doc_venv build
-
+# -----------------------------------------------------------------------
 # Catch-all target: route all unknown targets to Sphinx using the new
 # "make mode" option.  $(O) is meant as a shortcut for $(SPHINXOPTS).
-%: doc_venv Makefile
-	source $</bin/activate ; set -u ;\
-	$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
+# -----------------------------------------------------------------------
+docs-targets += html
 
+$(docs-targets) : $(venv-activate-script) Makefile
+	$(call banner-enter,Target $@)
+	$(activate) \
+	  && $(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
+	$(call banner-leave,Target $@)
+
+# [EOF]