[PATCH] Fix SMP build

Hi,

'make -j' fails usually because $(OBJDIR) was not created yet when
compiling files.

This patch adds a $(OBJDIR)/.dirstamp target which is added as a
dependency for object files and executes an 'mkdir'.

Recent CVS tries something like

| $(OBJDIR)/%:     $(OBJDIR)

but this does not work because:

* this dependency is ignored when more specific targets
  (e.g. '$(OBJDIR)/%.o') exist

* when it would work, it will cause rebuild of every file when timestamp
  of $(OBJDIR) changes.  This happens everytime when a new file is added.


See 

  http://github.com/ensc/dietlibc/commit/d9a9610d0eaaad1110691871b7d8544078a9e400.patch

for a patch against recent CVS.



Enrico