CVE-2026-43299 btrfs: do not ASSERT() when the fs flips RO inside btrfs_repair_io_failure()

In the Linux kernel, the following vulnerability has been resolved: btrfs: do not ASSERT when the fs flips RO inside btrfsrepairiofailure BUG There is a bug report that when btrfs hits ENOSPC error in a critical path, btrfs flips RO this part is expected, although the ENOSPC bug still needs to be...