Cleanup SLAPI namespace

servers/slapd/add.c

servers/slapd/backend.c

servers/slapd/bind.c

servers/slapd/compare.c

servers/slapd/config.c

servers/slapd/delete.c

servers/slapd/extended.c

servers/slapd/init.c

servers/slapd/main.c

servers/slapd/modify.c

servers/slapd/modrdn.c

servers/slapd/result.c

servers/slapd/root_dse.c

servers/slapd/search.c

servers/slapd/slapi/plugin.c

servers/slapd/slapi/printmsg.c

servers/slapd/slapi/proto-slapi.h

servers/slapd/slapi/slapi.h

servers/slapd/slapi/slapi_ext.c

servers/slapd/slapi/slapi_ops.c