perf parse-events: Use 'unsigned int' instead of plain 'unsigned'.

'unsigned int' should be clearer than 'unsigned'.
Signed-off-by: Xin Gao <gaoxin@cdjrlc.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220816174109.7718-1-gaoxin@cdjrlc.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/pmu.c

@@ -1182,7 +1182,7 @@ static char *pmu_formats_string(struct list_head *formats)
 	struct perf_pmu_format *format;
 	char *str = NULL;
 	struct strbuf buf = STRBUF_INIT;
-	unsigned i = 0;
+	unsigned int i = 0;
 
 	if (!formats)
 		return NULL;