x86/numa_emulation: Fix emulated-to-physical node mapping

Without this change the distance table calculation for emulated nodes
may use the wrong numa node and report an incorrect distance.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/153089328103.27680.14778434392225818887.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/mm/numa_emulation.c

@@ -61,7 +61,7 @@ static int __init emu_setup_memblk(struct numa_meminfo *ei,
 	eb->nid = nid;
 
 	if (emu_nid_to_phys[nid] == NUMA_NO_NODE)
-		emu_nid_to_phys[nid] = nid;
+		emu_nid_to_phys[nid] = pb->nid;
 
 	pb->start += size;
 	if (pb->start >= pb->end) {