dist: fix embedders autogen by adding standalone-makefiles to embedde…

…d tarball

Embedders don't get utils,tests,contrib/*,doc,... directories in their
tarball because they build hwloc in embedded mode.
However these tarballs cannot be re-autogen'ed unless they contain
all directories needed by automake even in non-embedded mode
(autogen doesn't know we're configuring hwloc in embedded or standalone mode).

OMPI didn't have any issue in the past because they manually copied
hwloc embedded directories AND created standalone subdirectories that
their automake would dist.
Now that they use hwloc as git submodule, bring the proper fix inside hwloc
so that OMPI doesn't have to hardwire that list of subdirectories anymore.

Refs open-mpi/ompi#7363

Note that pure-hwloc embedded tarballs still cannot be re-autogen'ed
because it needs many more standalone files
(everything used by configure, basically) but we do not care.

Signed-off-by: Brice Goglin <Brice.Goglin@inria.fr>
(cherry picked from commit ba6d413)

Makefile.am

@@ -71,7 +71,19 @@ endif
 if HWLOC_BUILD_STANDALONE
 dist-hook:
 	sh "$(top_srcdir)/config/distscript.sh" "$(top_srcdir)" "$(distdir)" "$(HWLOC_VERSION)"
-endif HWLOC_BUILD_STANDALONE
+else !HWLOC_BUILD_STANDALONE
+# Create directories needed by embedders' autogen (directories ignored by embedded dist)
+dist-hook:
+	@MKDIR_P@	\
+		$(distdir)/doc \
+		$(distdir)/netloc \
+		$(distdir)/utils \
+		$(distdir)/tests \
+		$(distdir)/contrib/hwloc-ps.www \
+		$(distdir)/contrib/misc \
+		$(distdir)/contrib/systemd \
+		$(distdir)/contrib/windows
+endif !HWLOC_BUILD_STANDALONE
 
 if HWLOC_BUILD_STANDALONE
 if HWLOC_HAVE_WINDOWS