mm/memory.c: use folios in __copy_remote_vm_str()

mm/memory.c: use folios in __copy_remote_vm_str()

Patch series "Remove unmap_and_put_page()".

This patchset uses folios in both the callers of unmap_and_put_page(),
saving a couple calls to compound_head() wrappers.

This patch (of 3):

Use kmap_local_folio() instead of kmap_local_page().  Replaces 2 calls to
compound_head() from unmap_and_put_page() with one.

This prepares us for the removal of unmap_and_put_page().

Link: https://lkml.kernel.org/r/20250709194017.927978-3-vishal.moola@gmail.com
Link: https://lkml.kernel.org/r/20250709194017.927978-4-vishal.moola@gmail.com
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Jordan Rome <linux@jordanrome.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>