mm/huge_memory: Fix xarray node memory leak

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

mm/huge_memory: Fix xarray node memory leak

If xas_split_alloc() fails to allocate the necessary nodes to complete the

xarray entry split, it sets the xa_state to -ENOMEM, which xas_nomem()

then interprets as "Please allocate more memory", not as "Please free

any unnecessary memory" (which was the intended outcome). It's confusing

to use xas_nomem() to free memory in this context, so call xas_destroy()

instead.