mm: Implement folio_remove_rmap_range()

Like page_remove_rmap() but batch-removes the rmap for a range of pages
belonging to a folio. This can provide a small speedup due to less
manipuation of the various counters. But more crucially, if removing the
rmap for all pages of a folio in a batch, there is no need to
(spuriously) add it to the deferred split list, which saves significant
cost when there is contention for the split queue lock.

All contained pages are accounted using the order-0 folio (or base page)
scheme.

Reviewed-by: Yin Fengwei <fengwei.yin@intel.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>