make pdfdoc errors with 4.12-rc2

[Jim Davis]

make pdfdocs, on my Fedora 25 desktop with the latest patches, fails with

Running Sphinx v1.5.2

[...lots-o-stuff...]

make PDFLATEX=xelatex LATEXOPTS="-interaction=batchmode" -C
Documentation/output/./latex || exit;
xelatex -interaction=batchmode 'linux-input.tex'
This is XeTeX, Version 3.14159265-2.6-0.99996 (TeX Live 2016)
(preloaded format=xelatex)
 restricted \write18 enabled.
entering extended mode
Makefile:67: recipe for target 'linux-input.pdf' failed
make[2]: *** [linux-input.pdf] Error 1
Documentation/Makefile.sphinx:87: recipe for target 'pdfdocs' failed
make[1]: *** [pdfdocs] Error 2
Makefile:1472: recipe for target 'pdfdocs' failed
make: *** [pdfdocs] Error 2


-- 
Jim