MAINTAINERS: add include/linux/pgalloc.h to MM CORE section

Patch series "mm: MISC follow-up patches for linux/pgalloc.h", v2.

This is a follow-up patch series for the patch series named: "[PATCH V5
mm-hotfixes 0/3] mm, x86: fix crash due to missing page table sync and
make it harder to miss".


This patch (of 2):

Since include/linux/pgtable.h is already listed in the MM CORE section,
add it to the section as well to keep it maintained by the appropriate
maintainers.

Link: https://lkml.kernel.org/r/20251024113047.119058-1-harry.yoo@oracle.com
Link: https://lkml.kernel.org/r/20251024113047.119058-2-harry.yoo@oracle.com
Signed-off-by: Harry Yoo <harry.yoo@oracle.com>
Acked-by: SeongJae Park <sj@kernel.org>
Acked-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>