$OpenBSD: patch-docs_Makefile,v 1.1 2016/04/16 19:06:25 shadchin Exp $
--- docs/Makefile.orig	Fri Apr 15 20:30:49 2016
+++ docs/Makefile	Fri Apr 15 20:30:53 2016
@@ -3,7 +3,7 @@
 
 # You can set these variables from the command line.
 SPHINXOPTS    =
-SPHINXBUILD   = sphinx-build
+SPHINXBUILD   ?= sphinx-build
 PAPER         =
 BUILDDIR      = _build
 
