perf tools: Fix a typo of command name as trace-cmd

Fix a typo which may be introduced when original code has been copied
from trace-cmd.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20111004104456.14591.37395.stgit@fedora15
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/trace-event-info.c

@@ -80,7 +80,7 @@ static void die(const char *fmt, ...)
 	int ret = errno;
 
 	if (errno)
-		perror("trace-cmd");
+		perror("perf");
 	else
 		ret = -1;