x86: set_highmem_pages_init() cleanup, #2

Impact: cleanup

The zones are set up at this stage so there's a highmem zone
available even for the UMA case.

The only difference there is that for machines that have
CONFIG_HIGHMEM enabled but don't have any highmem available,
->zone_start_pfn is zero whereas highstart_pfn is non-zero).

The field is left zeroed because of the !size test in
free_area_init_core() but shouldn't be a problem because
add_highpages_with_active_regions() handles empty ranges just
fine.
Signed-off-by: NPekka Enberg <penberg@cs.helsinki.fi>
Cc: Mel Gorman <mel@csn.ul.ie>
LKML-Reference: <1236154567.29024.23.camel@penberg-laptop>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

arch/x86/mm/highmem_32.c

@@ -158,7 +158,6 @@ EXPORT_SYMBOL(kunmap);
 EXPORT_SYMBOL(kmap_atomic);
 EXPORT_SYMBOL(kunmap_atomic);
 
-#ifdef CONFIG_NUMA
 void __init set_highmem_pages_init(void)
 {
 	struct zone *zone;
@@ -182,11 +181,3 @@ void __init set_highmem_pages_init(void)
 	}
 	totalram_pages += totalhigh_pages;
 }
-#else
-void __init set_highmem_pages_init(void)
-{
-	add_highpages_with_active_regions(0, highstart_pfn, highend_pfn);
-
-	totalram_pages += totalhigh_pages;
-}
-#endif /* CONFIG_NUMA */