rcu: Add documentation for raw SRCU read-side primitives

Update various files in Documentation/RCU to reflect srcu_read_lock_raw()
and srcu_read_unlock_raw().  Credit to Peter Zijlstra for suggesting
use of the existing _raw suffix instead of the earlier bulkref names.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
diff --git a/Documentation/RCU/rcu.txt b/Documentation/RCU/rcu.txt
index 3185270..bf77833 100644
--- a/Documentation/RCU/rcu.txt
+++ b/Documentation/RCU/rcu.txt
@@ -38,11 +38,11 @@
 
 	Preemptible variants of RCU (CONFIG_TREE_PREEMPT_RCU) get the
 	same effect, but require that the readers manipulate CPU-local
-	counters.  These counters allow limited types of blocking
-	within RCU read-side critical sections.  SRCU also uses
-	CPU-local counters, and permits general blocking within
-	RCU read-side critical sections.  These two variants of
-	RCU detect grace periods by sampling these counters.
+	counters.  These counters allow limited types of blocking within
+	RCU read-side critical sections.  SRCU also uses CPU-local
+	counters, and permits general blocking within RCU read-side
+	critical sections.  These variants of RCU detect grace periods
+	by sampling these counters.
 
 o	If I am running on a uniprocessor kernel, which can only do one
 	thing at a time, why should I wait for a grace period?