x86 numa: fix nodes' memory parsing when SRAT table includes future-hotplug memory...

x86 numa: fix nodes' memory parsing when SRAT table includes future-hotplug memory range

A node's future-hotplug memory range starts from very high end
normally, e.g. 1TB, and is not continuous with its current existing
memory range. It should not be covered by the global variable 'nodes'
as it assumes the node's memory is continuous. Otherwise it can make
nodes' memory ranges become very big and overlapped, and
populate_memnodemap() fails.

We can ignore future-hotplug memory range for now. Physical memory
hotplug support in future will handle it.

Signed-off-by: Yang Xiaowei <xiaowei.yang@intel.com>