perf metrics: Use 'unsigned int' instead of just 'unsigned'.

'unsigned int' should be clearer than 'unsigned'.

Signed-off-by: Xin Gao <gaoxin@cdjrlc.com>
Cc: Ian Rogers <irogers@google.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20220816173804.7539-1-gaoxin@cdjrlc.com


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>