* Makefile.in: Add targets to automatically rebuild dependencies.
Remove targets which just listed dependencies of .o files.
(DEP): New variable.
(HFILES, GENERATED_HFILES): New variables.
(CFILES, GENERATED_CFILES): New variables.
(underscore.c): Don't do anything, just depend upon stamp-under.
(stamp-under): New target; do what underscore.c used to do.
(nlmconv.o): Depend upon sym.h and ecoff.h.
(.dep, .dep1, dep.sed, dep, dep-in): New targets.
(stage1, stage2, stage3, against, comparison): Remove.
(de-stage1, de-stage2, de-stage3): Remove.
(clean, distclean): Remove stamp-under and dep.sed.
* dep-in.sed: New file.
* Makefile.in (OBJDUMP_OBJS): New variable.
($(OBJDUMP_PROG)): Use $(OBJDUMP_OBJS).