Notable changes:
* Commit 07bea2d35f ("block-backend: Remove deadcode") removed
blk_op_{,un}block_all() which was used by PVE async savevm code.
Fixed by switching to using bdrv_op_{,un}block_all().
* Drop patches that are already part of upstream.
Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
