sparc64: remove online_page()

The identical online_page() implementations from all architectures got 
moved to mm/memory_hotplug.c - except for the sparc64 one that even was 
dead code due to MEMORY_HOTPLUG not being available there.
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

arch/sparc64/mm/init.c

@@ -2362,16 +2362,3 @@ void __flush_tlb_all(void)
 	__asm__ __volatile__("wrpr	%0, 0, %%pstate"
 			     : : "r" (pstate));
 }
-
-#ifdef CONFIG_MEMORY_HOTPLUG
-
-void online_page(struct page *page)
-{
-	ClearPageReserved(page);
-	init_page_count(page);
-	__free_page(page);
-	totalram_pages++;
-	num_physpages++;
-}
-
-#endif /* CONFIG_MEMORY_HOTPLUG */