[SPARC]: enabling of the 2nd CPU in 2.6.18-rc4

smp_setup_cpu_possible_map() needs to run after paging_init()
so that the in-kernel device tree is setup.

Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>