ring-buffer-benchmark: Fix the wrong type

The macro 'module_param' shows that the type of the
variable disable_reader and write_iteration is unsigned
integer. so, we change their type form int to unsigned int.

Link: http://lkml.kernel.org/r/1433923927-67782-1-git-send-email-long.wanglong@huawei.com

Signed-off-by: Wang Long <long.wanglong@huawei.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

kernel/trace/ring_buffer_benchmark.c

@@ -32,11 +32,11 @@ static struct task_struct *producer;
 static struct task_struct *consumer;
 static unsigned long read;
 
-static int disable_reader;
+static unsigned int disable_reader;
 module_param(disable_reader, uint, 0644);
 MODULE_PARM_DESC(disable_reader, "only run producer");
 
-static int write_iteration = 50;
+static unsigned int write_iteration = 50;
 module_param(write_iteration, uint, 0644);
 MODULE_PARM_DESC(write_iteration, "# of writes between timestamp readings");