10428 loader: really fix cd9660 dirmatch
Review Request #1497 - Created Feb. 20, 2019 and submitted
The cd9660_open() does pass whole path to dirmatch() and we need to compare only the current path component, not full path. Additinally, skip over duplicate / (if any) and check if the last component in the path was meant to be directory (having trailing /). If it is in fact a file, error out.