[PATCH] powerpc numa: fix boot_cpuid always assigned to node 0

At boot, the numa code is assigning boot_cpuid to node 0
unconditionally.  Basically, numa_setup_cpu is being stupid about it,
but this is the minimal fix -- just call numa_setup_cpu(boot_cpuid)
later, after all nodes have been set online.

Signed-off-by: Nathan Lynch <nathanl@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>