cpu-sa11x0: CPUFREQ_ALL_CPUS shouldn't be passed as argument to
cpufreq_notify_transition() any more, but the exact CPU number.

mach-integrator: cpufreq_notify_transition() isn't called -- which
means that the transition notifiers are not informed. This patch adds
these callbacks. Also, CPUFREQ_ALL_CPUS can't passed to
cpufreq_driver->set_policy any longer, so some code can safely be
removed.