mm/vma: refactor vma_modify_flags_name() to vma_modify_name()

The single instance in which we use this function doesn't actually need to
change VMA flags, so remove this parameter and update the caller
accordingly.

[lorenzo.stoakes@oracle.com: correct comment]
  Link: https://lkml.kernel.org/r/77f45b2e-a748-4635-9381-a5051091087f@lucifer.local
Link: https://lkml.kernel.org/r/20250714135839.178032-1-lorenzo.stoakes@oracle.com


Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>