perf sched stats: Add support for live mode

perf sched stats: Add support for live mode

The live mode works similar to simple `perf stat` command, by profiling
the target and printing results on the terminal as soon as the target
finishes.

Example usage:

  # perf sched stats -- true
  Description
  ----------------------------------------------------------------------------------------------------
  DESC                          -> Description of the field
  COUNT                         -> Value of the field
  PCT_CHANGE                    -> Percent change with corresponding base value
  AVG_JIFFIES                   -> Avg time in jiffies between two consecutive occurrence of event
  ----------------------------------------------------------------------------------------------------

  Time elapsed (in jiffies)                                        :           1
  ----------------------------------------------------------------------------------------------------
  CPU: <ALL CPUS SUMMARY>
  ----------------------------------------------------------------------------------------------------
  DESC                                                                     COUNT   PCT_CHANGE
  ----------------------------------------------------------------------------------------------------
  yld_count                                                        :           0
  array_exp                                                        :           0
  sched_count                                                      :           0
  sched_goidle                                                     :           0  (     0.00% )
  ttwu_count                                                       :           0
  ttwu_local                                                       :           0  (     0.00% )
  rq_cpu_time                                                      :       27875
  run_delay                                                        :           0  (     0.00% )
  pcount                                                           :           0
  ----------------------------------------------------------------------------------------------------
  CPU: <ALL CPUS SUMMARY> | DOMAIN: SMT
  ----------------------------------------------------------------------------------------------------
  DESC                                                                     COUNT    AVG_JIFFIES
  ----------------------------------------- <Category busy> ------------------------------------------
  busy_lb_count                                                    :           0  $        0.00 $
  busy_lb_balanced                                                 :           0  $        0.00 $
  busy_lb_failed                                                   :           0  $        0.00 $
  busy_lb_imbalance_load                                           :           0
  busy_lb_imbalance_util                                           :           0
  busy_lb_imbalance_task                                           :           0
  busy_lb_imbalance_misfit                                         :           0
  busy_lb_gained                                                   :           0
  busy_lb_hot_gained                                               :           0
  busy_lb_nobusyq                                                  :           0  $        0.00 $
  busy_lb_nobusyg                                                  :           0  $        0.00 $
  *busy_lb_success_count                                           :           0
  *busy_lb_avg_pulled                                              :        0.00

  ... and so on. Output will show similar data for all the cpus in the
system.

Co-developed-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Swapnil Sapkal <swapnil.sapkal@amd.com>
Tested-by: Chen Yu <yu.c.chen@intel.com>
Tested-by: James Clark <james.clark@linaro.org>
Acked-by: Ian Rogers <irogers@google.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Anubhav Shelat <ashelat@redhat.com>
Cc: Ben Gainey <ben.gainey@arm.com>
Cc: Blake Jones <blakejones@google.com>
Cc: Chun-Tse Shao <ctshao@google.com>
Cc: David Vernet <void@manifault.com>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Dr. David Alan Gilbert <linux@treblig.org>
Cc: Gautham Shenoy <gautham.shenoy@amd.com>
Cc: Graham Woodward <graham.woodward@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@arm.com>
Cc: Madadi Vineeth Reddy <vineethr@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Santosh Shukla <santosh.shukla@amd.com>
Cc: Shrikanth Hegde <sshegde@linux.ibm.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Falcon <thomas.falcon@intel.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Yang Jihong <yangjihong@bytedance.com>
Cc: Yujie Liu <yujie.liu@intel.com>
Cc: Zhongqiu Han <quic_zhonhan@quicinc.com>
[ Avoid potentially using 'sv' uninitialized by calling free_cpu_domain_info() only when build_cpu_domain_map() is called ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>