Move all cpu map initializations to one place (except for the online map --
cpus mark themselves online as they come up).  This sets up
cpu_possible_map early enough that we can use num_possible_cpus for
allocating irqstacks instead of NR_CPUS.  Hopefully this should also help
set the stage for kexec.
Signed-off-by: Nathan Lynch <nathanl@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>