block: Add flags to bdrv(_co)_truncate()

Now that block drivers can support flags for .bdrv_co_truncate, expose
the parameter in the node level interfaces bdrv_co_truncate() and
bdrv_truncate().

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200424125448.63318-3-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block/vhdx-log.c

@@ -558,7 +558,7 @@ static int vhdx_log_flush(BlockDriverState *bs, BDRVVHDXState *s,
                     goto exit;
                 }
                 ret = bdrv_truncate(bs->file, new_file_size, false,
-                                    PREALLOC_MODE_OFF, NULL);
+                                    PREALLOC_MODE_OFF, 0, NULL);
                 if (ret < 0) {
                     goto exit;
                 }