Per-thread mode doesn't have specific CPUs for events, add checks for
this case.

Minor fix to a pr_debug by Ian Rogers <irogers@google.com> to avoid an
out of bound array access.

Fixes: 7954f716 ("perf record: Introduce thread affinity and mmap masks")
Reported-by: Ian Rogers <irogers@google.com>
Signed-off-by: Alexey Bayduraev <alexey.bayduraev@gmail.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20220414014642.3308206-1-irogers@google.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>