* nss/nss_db/db-XXX.c: Move internal_setent and internal_endent
functions from here...
* nss/db-alias.c: ...and here...
* nss/db-netgrp.c: ...and here...
* nss/nss_db/db-open.c: ...to here. New file.
* nss/nss_db/dummy-db.h: New file.
* nss/nss_db/nss_db.h: New file.
* nss/Depend: Depend in dlfcn, not db2.
* nss/Makefile (libnss_db-routines): Add db-open.
(distribute): Add nss_db.h dummy-db.h.
(libnss_db.so): Replace libdb dependency by $(libdl).
Based on a patch by Zack Weinberg.
