CVE-2025-68251

In the Linux kernel, the following vulnerability has been resolved:

erofs: avoid infinite loops due to corrupted subpage compact indexes

Robert reported an infinite loop observed by two crafted images.

The root cause is that `clusterofs` can be larger than `lclustersize`
for !NONHEAD `lclusters` in corrupted subpage compact indexes, e.g.:

  blocksize = lclustersize = 512   lcn = 6   clusterofs = 515

Move the corresponding check for full compress indexes to
`z_erofs_load_lcluster_from_disk()` to also cover subpage compact
compress indexes.

It also fixes the position of `m->type >= Z_EROFS_LCLUSTER_TYPE_MAX`
check, since it should be placed right after
`z_erofs_load_{compact,full}_lcluster()`.