Current best practice is to reuse the name of the function as a define to
indicate that the function is implemented by the architecture.

Link: https://lkml.kernel.org/r/20230802151406.3735276-6-willy@infradead.orgSigned-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>