sparc32: fix build errors

arch/sparc/kernel/sun4d_smp.c: In function ‘smp4d_callin’:
arch/sparc/kernel/sun4d_smp.c:101: error: implicit declaration of function ‘notify_cpu_starting’
arch/sparc/kernel/sun4m_smp.c: In function ‘smp4m_callin’:
arch/sparc/kernel/sun4m_smp.c:74: error: implicit declaration of function ‘notify_cpu_starting’

Signed-off-by: Robert Reif <reif@earthlink.net>
Signed-off-by: David S. Miller <davem@davemloft.net>