checkpoint: generate GIR information for NMCheckpointCreateFlags

Note that this changes API for checkpoint_create_async() in Python
via GIR. Previously it would require an integer argument, now a flags
argument. But this API is still unstable, it will be introduced with
1.12.

examples/python/gi/checkpoint.py

@@ -48,6 +48,7 @@ def do_create(client):
             sys.exit("Unknown device %s" % arg)
         devices.append(d)
 
+    # FIXME: flags are not a plain integer.
     client.checkpoint_create_async(devices, timeout, 0, None, create_cb, None)
 
 def destroy_cb(client, result, data):

libnm-core/nm-dbus-interface.h

@@ -857,9 +857,9 @@ typedef enum {
  *
  * The flags for CheckpointCreate call
  *
- * Since: 1.4
+ * Since: 1.4 (gi flags generated since 1.12)
  */
-typedef enum { /*< skip >*/
+typedef enum { /*< flags >*/
 	NM_CHECKPOINT_CREATE_FLAG_NONE                        = 0,
 	NM_CHECKPOINT_CREATE_FLAG_DESTROY_ALL                 = 0x01,
 	NM_CHECKPOINT_CREATE_FLAG_DELETE_NEW_CONNECTIONS      = 0x02,

libnm/libnm.ver

@@ -1334,6 +1334,7 @@ global:
 
 libnm_1_12_0 {
 global:
+	nm_checkpoint_create_flags_get_type;
 	nm_checkpoint_get_created;
 	nm_checkpoint_get_devices;
 	nm_checkpoint_get_rollback_timeout;