x86-64, NUMA: Wrap node ID during emulation

Both emulation layout functions - split_nodes[_size]_interleave() -
didn't wrap emulated nid while laying out the fake nodes and tried to
avoid interating over the specified number of nodes, which is fragile.

Now that the emulation code generates numa_meminfo, the node memblks
don't need to be consecutive and emulated node IDs can simply wrap.
This makes the code more robust and is necessary for updates to better
handle the cases where the physical nodes are interleaved.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>