WIP: arm64: reapply lost linkage between cpu capacity and freq caps

Thermal framework and other users are able to apply limits to the max
frequency allowed. The linkage to the scheduler's idea of the maximum
possible capacity for a given CPU is through scale_cpu_capacity in
topology.c but it lost the connection in a merge. Just reinstate it.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Srinath Sridharan <srinathsr@google.com>

bug: 28312446
Change-Id: I5caeb63a8c30cc8598fd0ae562d6ab3217c571ea

arch/arm64/kernel/topology.c

@@ -29,7 +29,13 @@ static DEFINE_PER_CPU(unsigned long, cpu_scale) = SCHED_CAPACITY_SCALE;
 
 unsigned long scale_cpu_capacity(struct sched_domain *sd, int cpu)
 {
+#ifdef CONFIG_CPU_FREQ
+	unsigned long max_cap_scale = cpufreq_scale_max_freq_capacity(cpu);
+
+	return per_cpu(cpu_scale, cpu) * max_cap_scale >> SCHED_CAPACITY_SHIFT;
+#else
 	return per_cpu(cpu_scale, cpu);
+#endif
 }
 
 static void set_capacity_scale(unsigned int cpu, unsigned long capacity)