Documentation/sphinx: build the media intermediate rst files for all outputs

This is a stopgap measure to allow building outputs other than html.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Acked-by: Markus Heiser <markus.heiser@darmarit.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Documentation/Makefile.sphinx

@@ -38,10 +38,9 @@ ALLSPHINXOPTS   = -D version=$(KERNELVERSION) -D release=$(KERNELRELEASE) -d $(B
 I18NSPHINXOPTS  = $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) .
 
 quiet_cmd_sphinx = SPHINX  $@
-      cmd_sphinx = BUILDDIR=$(BUILDDIR) $(SPHINXBUILD) -b $2 $(ALLSPHINXOPTS) $(BUILDDIR)/$2
+      cmd_sphinx = $(MAKE) BUILDDIR=$(BUILDDIR) $(build)=Documentation/media all; BUILDDIR=$(BUILDDIR) $(SPHINXBUILD) -b $2 $(ALLSPHINXOPTS) $(BUILDDIR)/$2
 
 htmldocs:
-	$(MAKE) BUILDDIR=$(BUILDDIR) -f $(srctree)/Documentation/media/Makefile $@
 	$(call cmd,sphinx,html)
 
 pdfdocs:

Documentation/media/Makefile

@@ -10,7 +10,8 @@ FILES = audio.h.rst ca.h.rst dmx.h.rst frontend.h.rst net.h.rst video.h.rst \
 
 TARGETS := $(addprefix $(BUILDDIR)/, $(FILES))
 
-htmldocs: $(BUILDDIR) ${TARGETS}
+.PHONY: all
+all: $(BUILDDIR) ${TARGETS}
 
 $(BUILDDIR):
 	$(Q)mkdir -p $@