KFileSystem: add FuseBlk and FuseBlk_BlockDevice types
The fuseblk filesystem type is used for various underlying filesystems, previously it was always treated as KFileSystemType::Nfs (i.e. treated as a potentially slow filesystem by e.g. KIO).
Instead add two types:
- FuseBlk
- FuseBlk_BlockDevice: this type is used if the fuseblk is on a local disk partition which uses the sd driver (/dev/sdXY), in that case this could be treated as a non-slow filesystem