cpumask: convert kernel trace functions further

Impact: Reduce future memory usage, use new cpumask API.

Since the last patch was created and acked, more old cpumask users
slipped into kernel/trace.

Mostly trivial conversions, except struct trace_iterator's "started"
member becomes a cpumask_var_t.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/kernel/trace/trace_hw_branches.c b/kernel/trace/trace_hw_branches.c
index b6a3e20..649df22 100644
--- a/kernel/trace/trace_hw_branches.c
+++ b/kernel/trace/trace_hw_branches.c
@@ -46,7 +46,7 @@
 
 	tracing_reset_online_cpus(tr);
 
-	for_each_cpu_mask(cpu, cpu_possible_map)
+	for_each_cpu(cpu, cpu_possible_mask)
 		smp_call_function_single(cpu, bts_trace_start_cpu, NULL, 1);
 }
 
@@ -62,7 +62,7 @@
 {
 	int cpu;
 
-	for_each_cpu_mask(cpu, cpu_possible_map)
+	for_each_cpu(cpu, cpu_possible_mask)
 		smp_call_function_single(cpu, bts_trace_stop_cpu, NULL, 1);
 }
 
@@ -172,7 +172,7 @@
 {
 	int cpu;
 
-	for_each_cpu_mask(cpu, cpu_possible_map)
+	for_each_cpu(cpu, cpu_possible_mask)
 		smp_call_function_single(cpu, trace_bts_cpu, iter->tr, 1);
 }