[linux-cifs-client] checking for rename of hardlinked files on windows

[Steve French]

in cifs_rename we check:

        if (rc == -EEXIST) {
                if (pTcon->unix_ext) {
                        /*
                         * Are src and dst hardlinks of same inode? We can
                         * only tell with unix extensions enabled

we could also add the same check for Windows (the UniqueId field is
supported by many servers)

-- 
Thanks,

Steve