s3-waf: use HAVE_ADS env to decide whether to build libads.so

Guenther

source3/wscript

@@ -910,6 +910,8 @@ return krb5_kt_resolve(context, "WRFILE:api", &keytab);
             conf.DEFINE('HAVE_KRB5', '1')
             if have_gssapi:
                 conf.DEFINE('HAVE_GSSAPI', '1')
+            if conf.CONFIG_SET('HAVE_LDAP'):
+                conf.env['HAVE_ADS'] = '1'
         else:
             Logs.warn("krb5 libs don't have all features required for Active Directory support")
             conf.undefine('HAVE_KRB5_H')

source3/wscript_build

@@ -819,9 +819,10 @@ bld.SAMBA3_SUBSYSTEM('SMBLDAP',
 
 bld.SAMBA3_LIBRARY('ads',
                    source=LIBADS_SRC,
-                   deps='LIBCLI_LDAP_NDR krb5',
+                   deps='LIBCLI_LDAP_NDR krb5 gssapi gssapi_krb5 ldap lber',
                    private_library=True,
-                   vars=locals())
+                   vars=locals(),
+                   enabled=bld.env.HAVE_ADS)
 
 bld.SAMBA3_SUBSYSTEM('LIBADS_SERVER',
                     source=LIBADS_SERVER_SRC,