DOC Document deprecating TotalItems()

Author: GuySartorelli

en/08_Changelogs/5.4.0.md

@@ -411,6 +411,8 @@ The exception was made for the following reasons:
 - [`CMSSiteTreeFilter::mapIDs()`](api:SilverStripe\CMS\Controllers\CMSSiteTreeFilter::mapIDs()) has been deprecated. It will be removed without equivalent functionality to replace it.
 - [`ElementSiteTreeFilterSearch`](api:DNADesign\Elemental\Controllers\ElementSiteTreeFilterSearch) has been deprecated. It will be replaced with `DNADesign\Elemental\ORM\Search\ElementalSiteTreeSearchContext`.
 - [`ElementalCMSMainExtension`](api:DNADesign\Elemental\Extensions\ElementalCMSMainExtension) has been deprecated. It will be removed without equivalent functionality to replace it.
+- [`ListDecorator::TotalItems()`](api:SilverStripe\ORM\ListDecorator::TotalItems()) has been deprecated. Use [`ListDecorator::getTotalItems()`](api:SilverStripe\ORM\ListDecorator::getTotalItems()) instead.
+- [`PaginatedList::TotalItems()`](api:SilverStripe\ORM\PaginatedList::TotalItems()) has been deprecated. Use [`PaginatedList::getTotalItems()`](api:SilverStripe\ORM\PaginatedList::getTotalItems()) instead.
 
 ## Bug fixes