rcu: Make rcu update module parameters world-readable

rcu update module parameters currently don't appear in sysfs and this is
a serviceability issue as it might be needed to access their default
values at runtime.

Fix this issue by changing rcu update module parameters permissions to
world-readable.
Suggested-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

kernel/rcu/update.c

@@ -54,11 +54,11 @@
 #define MODULE_PARAM_PREFIX "rcupdate."
 
 #ifndef CONFIG_TINY_RCU
-module_param(rcu_expedited, int, 0);
-module_param(rcu_normal, int, 0);
+module_param(rcu_expedited, int, 0444);
+module_param(rcu_normal, int, 0444);
 static int rcu_normal_after_boot = IS_ENABLED(CONFIG_PREEMPT_RT);
 #if !defined(CONFIG_PREEMPT_RT) || defined(CONFIG_NO_HZ_FULL)
-module_param(rcu_normal_after_boot, int, 0);
+module_param(rcu_normal_after_boot, int, 0444);
 #endif
 #endif /* #ifndef CONFIG_TINY_RCU */