docs: Update HTML markup(s).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137433 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/docs/LangRef.html b/docs/LangRef.html
index 583ef83..b20f085 100644
--- a/docs/LangRef.html
+++ b/docs/LangRef.html
@@ -1576,11 +1576,11 @@
 </div>
 
 <!-- ======================================================================= -->
-<div class="doc_subsection">
+<h3>
       <a name="ordering">Atomic Memory Ordering Constraints</a>
-</div>
+</h3>
 
-<div class="doc_text">
+<div>
 
 <p>Atomic instructions (<a href="#i_cmpxchg"><code>cmpxchg</code></a>,
 <a href="#i_atomicrmw"><code>atomicrmw</code></a>,
@@ -4709,10 +4709,11 @@
 </div>
 
 <!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection"> <a name="i_fence">'<tt>fence</tt>'
-Instruction</a> </div>
+<h4>
+<a name="i_fence">'<tt>fence</tt>' Instruction</a>
+</h4>
 
-<div class="doc_text">
+<div>
 
 <h5>Syntax:</h5>
 <pre>
@@ -4763,10 +4764,11 @@
 </div>
 
 <!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection"> <a name="i_cmpxchg">'<tt>cmpxchg</tt>'
-Instruction</a> </div>
+<h4>
+<a name="i_cmpxchg">'<tt>cmpxchg</tt>' Instruction</a>
+</h4>
 
-<div class="doc_text">
+<div>
 
 <h5>Syntax:</h5>
 <pre>
@@ -4845,10 +4847,11 @@
 </div>
 
 <!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection"> <a name="i_atomicrmw">'<tt>atomicrmw</tt>'
-Instruction</a> </div>
+<h4>
+<a name="i_atomicrmw">'<tt>atomicrmw</tt>' Instruction</a>
+</h4>
 
-<div class="doc_text">
+<div>
 
 <h5>Syntax:</h5>
 <pre>