[docs] Fix rst title in clang langext docs. NFCI
Fix an odd line in LanguageExtensions.rst which
rendered incorrectly due to an underscore being
mixed in with dashes.
llvm-svn: 357793
diff --git a/clang/docs/LanguageExtensions.rst b/clang/docs/LanguageExtensions.rst
index d79d412..0299dde 100644
--- a/clang/docs/LanguageExtensions.rst
+++ b/clang/docs/LanguageExtensions.rst
@@ -1791,7 +1791,7 @@
by the name of the builtin.
``__builtin_rotateright``
-_------------------------
+-------------------------
* ``__builtin_rotateright8``
* ``__builtin_rotateright16``