Revert "poky: subtree update:b23aa6b753..ad30a6d470"

This reverts commit af5e4ef732faedf66c6dc1756432e9de2ac72988.

This commit introduced openbmc/openbmc#3720 and no solution has been
forthcoming. Revert until we can get to the bottom of this.

Change-Id: I2fb0d81eb26cf3dadb2f2abdd1a1bb7a95eaf03c
diff --git a/poky/documentation/README b/poky/documentation/README
index fe86876..fce3cfe 100644
--- a/poky/documentation/README
+++ b/poky/documentation/README
@@ -121,7 +121,7 @@
 To build the documentation locally, run:
 
  $ cd documentation
- $ make html
+ $ make -f Makefile.sphinx html
 
 The resulting HTML index page will be _build/html/index.html, and you
 can browse your own copy of the locally generated documentation with