Prevent fake NTFS filesystems to appear in the filesystem mounts #1519
Description
A few loaders use loaderutil.add_virtual_ntfs_filesystem() to add a virtual NTFS filesystem. When using this functionality, a "fake" NTFS filesystem is added. This filesystem contains references to the $MFT, $UsnJrnl etc. This filesystem is used for NTFS-specific plugins. The added "fake" virtual NTFS filesystems can only be used by plugins, not for mount points.
When using target-mount on a target for which loaderutil.add_virtual_ntfs_filesystem() is used, this leads to entries in fs/$fs$/ . This issue is reported as issue #1457.
However, it also leads to entries in filesystems (such as filesystems/fs_1).
Target-mount should create mounts in filesystems/ for the virtual filesystems which have a "fake" NTFS filesystem attached. It should not create mounts in filesystems/ for these "fake" NTFS filesystems themselves.