[VOL-5338] - Add support for pre-commit tool and repo:onf-make

 .pre-commit-config.yaml
 -----------------------
   o Add basic tool config

makfiles/include.mk
makefiles/commands/pre-commit/
requirements.txt
------------------------------
  o virtualenv: install python module pre-commit.
  o Add makefile target 'pre-commit' to install venv and
    pre-commit tool by dependency.

Signed-off-by: Joey Armstrong <jarmstrong@linuxfoundation.org>
Change-Id: I7c3e4b46cab429e60e504e5f9579d578614eafad
diff --git a/makefiles/include.mk b/makefiles/include.mk
index 6091502..e95c9b7 100644
--- a/makefiles/include.mk
+++ b/makefiles/include.mk
@@ -33,6 +33,8 @@
 onf-mk-top    := $(subst /include.mk,$(null),$(onf-mk-abs))
 ONF_MAKEDIR   := $(onf-mk-top)
 
+onf-mk-dir    ?= $(onf-mk-top)#              # fodder for transition.mk
+
 include $(ONF_MAKEDIR)/consts.mk
 include $(ONF_MAKEDIR)/help/include.mk       # render target help
 include $(ONF_MAKEDIR)/utils/include.mk      # dependency-less helper macros
@@ -43,6 +45,8 @@
 # include $(ONF_MAKEDIR)/git-submodules.mk
 # include $(ONF_MAKEDIR)/gerrit/include.mk
 
+include $(ONF_MAKEDIR)/commands/pre-commit/include.mk
+
 include $(ONF_MAKEDIR)/todo.mk
 include $(ONF_MAKEDIR)/help/variables.mk