rcu: Rename rcu_lockdep_assert() to RCU_LOCKDEP_WARN()

This commit renames rcu_lockdep_assert() to RCU_LOCKDEP_WARN() for
consistency with the WARN() series of macros.  This also requires
inverting the sense of the conditional, which this commit also does.

Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
diff --git a/kernel/pid.c b/kernel/pid.c
index 4fd07d5..ca36879 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -451,9 +451,8 @@
  */
 struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns)
 {
-	rcu_lockdep_assert(rcu_read_lock_held(),
-			   "find_task_by_pid_ns() needs rcu_read_lock()"
-			   " protection");
+	RCU_LOCKDEP_WARN(!rcu_read_lock_held(),
+			 "find_task_by_pid_ns() needs rcu_read_lock() protection");
 	return pid_task(find_pid_ns(nr, ns), PIDTYPE_PID);
 }