don't link libxfr unless prerequisites are met.

git-svn-id: svn://bind10.isc.org/svn/bind10/trunk@1638 e5f2f494-b856-4b98-b285-d166d9295462

src/bin/auth/Makefile.am

@@ -33,8 +33,10 @@ b10_auth_LDADD += $(top_builddir)/src/lib/config/.libs/libcfgclient.a
 b10_auth_LDADD += $(top_builddir)/src/lib/cc/libcc.a
 b10_auth_LDADD += $(top_builddir)/src/lib/exceptions/.libs/libexceptions.a
 b10_auth_LDADD += $(SQLITE_LIBS)
-b10_auth_LDADD += $(top_builddir)/src/lib/xfr/.libs/libxfr.a
 if HAVE_BOOST_SYSTEM
+if HAVE_BOOST_PYTHON
+b10_auth_LDADD += $(top_builddir)/src/lib/xfr/.libs/libxfr.a
+endif
 b10_auth_LDFLAGS = $(AM_LDFLAGS) $(BOOST_LDFLAGS)
 b10_auth_LDADD += $(BOOST_SYSTEM_LIB)
 endif