net-dns/bind: add use flags in metadata

Signed-off-by: Victor Kustov <ktrace@yandex.ru>

net-dns/bind/metadata.xml

@@ -6,4 +6,15 @@
         <name>Mir Calculate</name>
         <description>Calculate Overlay</description>
     </maintainer>
+    <use>
+        <flag name="dnstap">Enables dnstap packet logging</flag>
+        <flag name="dnsrps">Enable the DNS Response Policy Service (DNSRPS) API, a mechanism to allow an external response policy provider</flag>
+        <flag name="dlz">Enables dynamic loaded zones, 3rd party extension</flag>
+        <flag name="fixed-rrset">Enables fixed rrset-order option</flag>
+        <flag name="geoip2">Enable GeoIP2 API from MaxMind</flag>
+        <flag name="gssapi">Enable gssapi support</flag>
+        <flag name="json">Enable JSON statistics channel</flag>
+        <flag name="lmdb">Enable LMDB support to store configuration for 'addzone' zones</flag>
+        <flag name=sdb-ldap>Use LDAP backend</flag>
+    </use>
 </pkgmetadata>