r14325: Add pam_modules rule which builds the configure(d) pam modules. This is
called as part of the all rule (again only if pam modules are requested
by configure).
Add pam_winbind rule.
Ensure proto_exists before we build the pam modules.
Add test_pam_modules rule to test if the built pam modules have any
unresolved symbols. For test_pam_modules we use script/tests/dlopen.sh
which was written by Nalin Dahyabhai <nalin@redhat.com>. Thanks Nalin!
RedHat and SuSE use this script to test nss and pam modules since
several years.