'make distribution' fails w/'ro' /usr/obj

[Matthew Dillon]

:make distribution will touch targets which are not built during buildworl=
:d (heh, yea.)  specifically, etc/Makefile and associates prepare config f=
:iles.  maybe we should hook this into the build as well?
:
:cheers
:  simon

     It's not critical for this release but I think its a fine idea.  Still,
     rather then incorporate it into the buildworld I'd suggest creating
     a make builddistribution target which covers the extra bits so 
     make distribution can then run without further modifications to /usr/obj.

						-Matt