block: drop bdrv_remove_filter_or_cow_child

Drop this simple wrapper used only in one place. We have too many graph
modifying functions even without it.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@openvz.org>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20221107163558.618889-3-vsementsov@yandex-team.ru>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
diff --git a/block.c b/block.c
index c0c1b3d..dc76120 100644
--- a/block.c
+++ b/block.c
@@ -93,8 +93,6 @@
 static void bdrv_replace_child_noperm(BdrvChild *child,
                                       BlockDriverState *new_bs);
 static void bdrv_remove_child(BdrvChild *child, Transaction *tran);
-static void bdrv_remove_filter_or_cow_child(BlockDriverState *bs,
-                                            Transaction *tran);
 
 static int bdrv_reopen_prepare(BDRVReopenState *reopen_state,
                                BlockReopenQueue *queue,
@@ -5065,17 +5063,6 @@
     tran_add(tran, &bdrv_remove_child_drv, child);
 }
 
-/*
- * A function to remove backing-chain child of @bs if exists: cow child for
- * format nodes (always .backing) and filter child for filters (may be .file or
- * .backing)
- */
-static void bdrv_remove_filter_or_cow_child(BlockDriverState *bs,
-                                            Transaction *tran)
-{
-    bdrv_remove_child(bdrv_filter_or_cow_child(bs), tran);
-}
-
 static int bdrv_replace_node_noperm(BlockDriverState *from,
                                     BlockDriverState *to,
                                     bool auto_skip, Transaction *tran,
@@ -5160,7 +5147,7 @@
     }
 
     if (detach_subchain) {
-        bdrv_remove_filter_or_cow_child(to_cow_parent, tran);
+        bdrv_remove_child(bdrv_filter_or_cow_child(to_cow_parent), tran);
     }
 
     found = g_hash_table_new(NULL, NULL);