CVE-2026-68343: smb: client: validate DFS referral PathConsumed

In the Linux kernel, the following vulnerability has been resolved: smb: client: validate DFS referral PathConsumed parse_dfs_referrals() validates that the response contains the fixed referral entry array and, on for-next, the per-referral string offsets. However, the response also contains a PathConsumed value that is later used for DFS path parsing. If a malformed response provides a PathConsumed value larger than the search name, later DFS parsing can advance beyond the end of the path. Validate PathConsumed against the search name length before storing it in the parsed referral.