[krbdev.mit.edu #2962] @MAINT@ references in Makefile.in files do not work on Windows

[Jeffrey Altman via RT]

There are three Makefile.in files which contain @MAINT@ build
dependencies.  wconfig.c does not process @MAINT@ out of the file as 
expected.  Therefore, the tree fails to build.

One work around for this is to use Makefile variables for the dependency
list and provide overrides for ##WIN##

Another solution would be to modify wconfig.c to parse @MAINT@ out of
lines it is found in.

This must be fixed for 1.4.1