[VOL-5308] - bbsim test failure

Makefile
--------
  o Temporary flag USE_LF_MK=1 added to enable library repo:onf-make use.
  o Default behavior will use legacy makefiles from  repo:bbsim/makefiles/.
  o Fixed typo on line 76

lf/include.mk
makefiles/
-------------
  o Transition bridge for using repo:onf-make.
  o Define variable legacy-mk= as bbsim/makefiles/
  o Replace path variable $(MAKEDIR=) with $(legacy-mk).
  o Replace variable $(ONF_MAKEDIR=) with $(legacy-mk).
  o These edits help break dependency on non-library makefiles/ directory.
    allowing repo:onf-make to be used as a transparent replacement.

Change-Id: Ida8c020384cf78ddf19fa6375702429d992d10a1
Signed-off-by: Joey Armstrong <jarmstrong@linuxfoundation.org>
diff --git a/docs/Makefile b/docs/Makefile
index 462d7ce..bd8194d 100644
--- a/docs/Makefile
+++ b/docs/Makefile
@@ -26,6 +26,7 @@
    )\
 )
 TOP-docs := $(subst /docs/,$(null),$(TOP-docs))
+legacy-mk ?= $(TOP-docs)/makefiles
 
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