perf tests: Check proper prev_state size for sched_switch tp

The prev_state is defined as long which is 4 bytes long on 32-bit x86.
Changing the check against sizeof(long).

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1373639346-4547-1-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/tests/evsel-tp-sched.c

@@ -49,7 +49,7 @@ int test__perf_evsel__tp_sched_test(void)
 	if (perf_evsel__test_field(evsel, "prev_prio", 4, true))
 		ret = -1;
 
-	if (perf_evsel__test_field(evsel, "prev_state", 8, true))
+	if (perf_evsel__test_field(evsel, "prev_state", sizeof(long), true))
 		ret = -1;
 
 	if (perf_evsel__test_field(evsel, "next_comm", 16, true))