kmemtrace: Fix up tracer registration

Commit ddc1637a ("kmemtrace: Print
binary output only if 'bin' option is set") ended up inverting the
error detection logic. register_tracer() returns 0 on success,
which this change caused to treat as an error, resulting in:

[    0.132000] Warning: could not register the kmem tracer

as well as bailing out of the initcall with an error value. This
restores the old logic.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <20090928075540.GD6668@linux-sh.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/trace/kmemtrace.c

@@ -501,7 +501,7 @@ static int __init init_kmem_tracer(void)
 		return 1;
 	}
 
-	if (!register_tracer(&kmem_tracer)) {
+	if (register_tracer(&kmem_tracer) != 0) {
 		pr_warning("Warning: could not register the kmem tracer\n");
 		return 1;
 	}