Stop generating per-directory sed scripts, and use perl to compute the patterns

Stop generating per-directory sed scripts, and use perl to compute the patterns
on the fly instead.  (Next step, someday, integrate this script and depfix.sed,
so we only have to run one script.)

* config/post.in (depend-dependencies): Use (and depend on) depfix2.pl instead
of .depfix2.sed.
(.depfix2.sed): Target deleted.
(DEPTARGETS): Delete .depfix2.sed and .depfix2.tmp.
* util/depgen.sed: Deleted.
* util/depfix2.pl: New file.

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@17187 dc483132-0cff-0310-8789-dd5450dbe970