BOOL ntfs_check_logfile (struct inode * log_vi);
Check the $LogFile journal for consistency and return TRUE if it is consistent and FALSE if not.
At present we only check the two restart pages and ignore the log record pages.
Note that the MstProtected flag is not set on the $LogFile inode and hence when reading pages they are not deprotected. This is because we do not know if the $LogFile was created on a system with a different page size to ours yet and mst deprotection would fail if our page size is smaller.