Changing a code block to text because Sphinx does not like it on the …

…builder (http://lab.llvm.org:8011/builders/llvm-sphinx-docs/builds/12517/steps/docs-llvm-html/logs/stdio)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@280247 91177308-0d34-0410-b5e6-96231b3b80d8

docs/Coroutines.rst

@@ -812,7 +812,7 @@ pointer that was returned by prior `coro.begin` call.
 Example (custom deallocation function):
 """""""""""""""""""""""""""""""""""""""
 
-.. code-block:: llvm
+.. code-block:: text
 
   cleanup:
     %mem = call i8* @llvm.coro.free(token %id, i8* %frame)
@@ -827,7 +827,7 @@ Example (custom deallocation function):
 Example (standard deallocation functions):
 """"""""""""""""""""""""""""""""""""""""""
 
-.. code-block:: llvm
+.. code-block:: text
 
   cleanup:
     %mem = call i8* @llvm.coro.free(token %id, i8* %frame)