Revert https://trac.osgeo.org/grass/changeset/48813 to avoid race condition in parallel builds

Declare images as secondary targets to avoid deletion



git-svn-id: https://svn.osgeo.org/grass/grass/trunk@49455 15284696-431f-4ddb-bdfa-cd5b030d7da7

include/Make/Html.make

@@ -12,10 +12,11 @@ htmldesc = $(call run_grass,$(1) --html-description < /dev/null | grep -v '</bod
 IMGSRC := $(wildcard *.png) $(wildcard *.jpg)
 IMGDST := $(patsubst %,$(HTMLDIR)/%,$(IMGSRC))
 
-$(HTMLDIR)/%.html: %.html %.tmp.html $(HTMLSRC) | $(HTMLDIR)
+$(HTMLDIR)/%.html: %.html %.tmp.html $(HTMLSRC) $(IMGDST) | $(HTMLDIR)
 	$(PYTHON) $(GISBASE)/tools/mkhtml.py $* $(GRASS_VERSION_DATE) > $@
+
 ifneq ($(strip $(IMGDST)),)
-	$(MAKE) $(IMGDST)
+.SECONDARY: $(IMGDST)
 endif
 
 $(HTMLDIR)/%.png: %.png | $(HTMLDIR)