Revert "Treat warnings in Sphinx as errors. The reasons for doing thi…

…s are..."

This reverts commit r213661.

Reverting at the request of Sean Silva.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213675 91177308-0d34-0410-b5e6-96231b3b80d8

docs/Makefile.sphinx

@@ -10,7 +10,7 @@ BUILDDIR      = _build
 # Internal variables.
 PAPEROPT_a4     = -D latex_paper_size=a4
 PAPEROPT_letter = -D latex_paper_size=letter
-ALLSPHINXOPTS   = -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) -W .
+ALLSPHINXOPTS   = -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) .
 # the i18n builder cannot share the environment and doctrees with the others
 I18NSPHINXOPTS  = $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) .