Get static linking working again, mostly

Get static linking working again, mostly

Static linking (#6510) broke when lockout support was added because
the DB2 plugin became dependent on libkadm5srv_mit for XDR functions.
Also, static linking was extensively broken in combination with LDAP
support.  Fix these problems.

Afer these fixes, the test suite fails in the FAST tests because
there's no static build support for dynamic preauth plugins, which
means there's no encrypted challenge.  (And unlike the pkinit tests,
the test suite doesn't conditionalize on the presence of the encrypted
challenge plugin, because we always build it.)  This will fix itself
if and when encrypted challenge becomes linked into the consumers, or
static build support is added for preauth plugins.

ticket: 6914

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@24996 dc483132-0cff-0310-8789-dd5450dbe970