powerpc/mm: Use common paging_init() for NUMA

Commit 1c98025c6c95bc057a25e2c6596de23288c68160 "powerpc: Dynamic DMA
zone limits" updated how zones are created in paging_init(), but missed
the NUMA version of paging_init(). This was noticed via a linker
error, since dma_pfn_limit_to_zone() was, like the non-NUMA
paging_init(), limited by #ifndef CONFIG_NEED_MULTIPLE_NODES.

It turns out that the NUMA paging_init() was not actually doing
anything different from the standard paging_init(), other than a couple
debug prints, a couple 32-bit-only ifdef sections, and a call to
mark_nonram_nosave(). It's not clear whether mark_nonram_nosave() is
inherently wrong to do for NUMA, or just not useful on targets that
have NUMA, but for now I'm preserving the existing behavior.

Fixes: 1c98025c6c9 "powerpc: Dynamic DMA zone limits"
Reported-by: Stephen Rothwell <[e-mail]>
Signed-off-by: Scott Wood <[e-mail]>

arch/powerpc/mm/mem.c

···
 	}
 	return 0;
 }
+#else /* CONFIG_NEED_MULTIPLE_NODES */
+static int __init mark_nonram_nosave(void)
+{
+	return 0;
+}
+#endif
 
 static bool zone_limits_final;
 
···
 
 	mark_nonram_nosave();
 }
-#endif /* ! CONFIG_NEED_MULTIPLE_NODES */
 
 static void __init register_page_bootmem_info(void)
 {

arch/powerpc/mm/numa.c

···
 			  (void *)(unsigned long)boot_cpuid);
 }
 
-void __init paging_init(void)
-{
-	unsigned long max_zone_pfns[MAX_NR_ZONES];
-	memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
-	max_zone_pfns[ZONE_DMA] = memblock_end_of_DRAM() >> PAGE_SHIFT;
-	free_area_init_nodes(max_zone_pfns);
-}
-
 static int __init early_numa(char *p)
 {
 	if (!p)