x86/mm/pat: Convert pte code to use page table apis

x86/mm/pat: Convert pte code to use page table apis

Use the ptdesc APIs for all page table allocation and free sites to allow
their separate allocation from struct page in the future. Convert the PTE
allocation and free sites to use the generic page table APIs, as they
already use ptdescs.

Pass through init_mm since these are kernel page tables; otherwise,
pte_alloc_one_kernel() becomes a no-op.

Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Link: https://patch.msgid.link/20260303194828.1406905-2-vishal.moola@gmail.com