CVE-2026-97548: In the Linux kernel, the following vulnerability has been resolved: xfs: fix the rtrmap and rtrefcount _maxlevels_ondis

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

xfs: fix the rtrmap and rtrefcount _maxlevels_ondisk functions

The _maxlevels_ondisk functions are used to compute the size of in-memory btree cursors for each btree type. Unfortunately, LOLLM noticed that the rtrmap and rtrefcount versions of these functions forget to account for the inode root, which means that we could access beyond the end of the cursor given a sufficiently large btree. Fix this.