Have make a makefile to store info files in a hardwired directory
$(infdir). How would I make the user supply the command to run
the info generation? Something like "make -f myfile.mk info-option"
.SECONDEXPANSION: # Enable second expansion of $(@D)
$(infdir)/antares.info: $(srcs) | $$(@D)
makeinfo $(opts) -o $@ $<
