md: check for memory allocation failure in faulty personality

It's a fault injection module, but I don't think we should oops here.
Signed-off-by: Sven Wegener <sven.wegener@stealer.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Neil Brown <neilb@suse.de>

drivers/md/faulty.c

@@ -287,6 +287,8 @@ static int run(mddev_t *mddev)
 	int i;
 
 	conf_t *conf = kmalloc(sizeof(*conf), GFP_KERNEL);
+	if (!conf)
+		return -ENOMEM;
 
 	for (i=0; i<Modes; i++) {
 		atomic_set(&conf->counters[i], 0);