perf test: JSON format checking

Add field checking tests for perf stat JSON output.

Sanity checks the expected number of fields are present, that the
expected keys are present and they have the correct values.

Committer notes:

Had to fix this:

  -               $(INSTALL) tests/shell/lib/*.sh '$(DESTDIR_SQ)$(perfexec_instdir_SQ)/tests/shell/lib' \
  +               $(INSTALL) tests/shell/lib/*.sh '$(DESTDIR_SQ)$(perfexec_instdir_SQ)/tests/shell/lib'; \

Committer testing:

  [root@quaco ~]# perf test json
   90: perf stat JSON output linter                                    : Ok
  [root@quaco ~]# set -o vi
  [root@quaco ~]# perf test -v json
   90: perf stat JSON output linter                                    :
  --- start ---
  test child forked, pid 560794
  Checking json output: no args [Success]
  Checking json output: system wide [Success]
  Checking json output: system wide Checking json output: system wide no aggregation [Success]
  Checking json output: interval [Success]
  Checking json output: event [Success]
  Checking json output: per core [Success]
  Checking json output: per thread [Success]
  Checking json output: per die [Success]
  Checking json output: per node [Success]
  Checking json output: per socket [Success]
  test child finished with 0
  ---- end ----
  perf stat JSON output linter: Ok
  [root@quaco ~]#

Signed-off-by: Claire Jensen <cjense@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alyssa Ross <hi@alyssa.is>
Cc: Claire Jensen <clairej735@gmail.com>
Cc: Florian Fischer <florian.fischer@muhq.space>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Like Xu <likexu@tencent.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Xing Zhengjun <zhengjun.xing@linux.intel.com>
Link: https://lore.kernel.org/r/20220805200105.2020995-3-irogers@google.com
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>