bind: fix configure in case lmdb devel files are present on the host

Fix configure failure in case lmdb devel files are present on the host
by adding --without-lmdb option (reported [1] and fix tested [2],[3] by
grunpferd@netscape.net).

Fixes:

  checking for lmdb library... yes
  checking for library containing mdb_env_create... no
  configure: error: found lmdb include but not library.

[1] http://lists.busybox.net/pipermail/buildroot/2017-August/199945.html
[2] http://lists.busybox.net/pipermail/buildroot/2017-August/199963.html
[3] http://lists.busybox.net/pipermail/buildroot/2017-August/199964.html

Signed-off-by: Peter Seiderer <ps.report@gmx.net>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>

package/bind/bind.mk

@@ -24,6 +24,7 @@ BIND_CONF_ENV = \
 	BUILD_CC="$(TARGET_CC)" \
 	BUILD_CFLAGS="$(TARGET_CFLAGS)"
 BIND_CONF_OPTS = \
+	--without-lmdb \
 	--with-libjson=no \
 	--with-randomdev=/dev/urandom \
 	--enable-epoll \