ACPI: NUMA: Remove the useless 'node >= MAX_NUMNODES' check

acpi_map_pxm_to_node() will never return a NUMA node greater than
MAX_NUMNODES, so the 'node >= MAX_NUMNODES' check is not needed.
Remove it.

Signed-off-by: Hanjun Guo <guohanjun@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>