cifs: fix smb1 mount regression

cifs.ko maps NT_STATUS_NOT_FOUND to -EIO when SMB1 servers couldn't
resolve referral paths.  Proceed to tree connect when we get -EIO from
dfs_get_referral() as well.

Reported-by: Kris Karas (Bug Reporting) <bugs-a21@moonlit-rail.com>
Tested-by: Woody Suwalski <terraluna977@gmail.com>
Fixes: 8e35541 ("cifs: fix sharing of DFS connections")
Cc: stable@vger.kernel.org # v6.2+
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Author: Paulo Alcantara

fs/cifs/dfs.c

@@ -303,7 +303,7 @@ int dfs_mount_share(struct cifs_mount_ctx *mnt_ctx, bool *isdfs)
 	if (!nodfs) {
 		rc = dfs_get_referral(mnt_ctx, ctx->UNC + 1, NULL, NULL);
 		if (rc) {
-			if (rc != -ENOENT && rc != -EOPNOTSUPP)
+			if (rc != -ENOENT && rc != -EOPNOTSUPP && rc != -EIO)
 				goto out;
 			nodfs = true;
 		}