selinux: Don't include unused reference count in verbose logging

libselinux 3.8 includes an API break in which the `refcnt` field of
struct security_id_t (originally intended to be a reference count, but
in practice always initialized to 1 and never modified) was renamed and
repurposed as an `id` field. This caused a build failure if dbus was
compiled with both SELinux support and verbose mode, for example in the
instrumented debug build that Debian includes in the `dbus-tests` package.

This particular piece of debug logging has little value, so just
remove it.

Reference: e5fd7b078f
Bug-Debian: https://bugs.debian.org/1096212
Signed-off-by: Simon McVittie <smcv@collabora.com>

bus/selinux.c

@@ -925,7 +925,6 @@ bus_selinux_id_table_print (DBusHashTable *service_table)
       security_id_t sid = _dbus_hash_iter_get_value (&iter);
       _dbus_verbose ("The key is %s\n", key);
       _dbus_verbose ("The context is %s\n", sid->ctx);
-      _dbus_verbose ("The refcount is %d\n", sid->refcnt);
     }
 #endif /* DBUS_ENABLE_VERBOSE_MODE && HAVE_SELINUX */
 }