CVE-2026-64326 block: skip sync_blockdev() on surprise removal in bdev_mark_dead()

In the Linux kernel, the following vulnerability has been resolved: block: skip syncblockdev on surprise removal in bdevmarkdead bdevmarkdead's @surprise == true means the device is already gone. The filesystem callback fsbdevmarkdead honours this and skips syncfilesystem, but the bare block devi...