perf report: Fix warning assignment of 0/1 to bool variable

perf report: Fix warning assignment of 0/1 to bool variable

Fixes coccicheck warning:

  tools/perf/builtin-report.c:1403:2-34: WARNING: Assignment of 0/1 to bool variable

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zou Wei <zou_wei@huawei.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/1587904683-3510-1-git-send-email-zou_wei@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>