[AMDGPU][MC][DOC] A fix for build failure in r349370

llvm-svn: 349375
diff --git a/llvm/docs/AMDGPU/gfx7_src_exp.rst b/llvm/docs/AMDGPU/gfx7_src_exp.rst
index 6d155a5..32f71a8 100644
--- a/llvm/docs/AMDGPU/gfx7_src_exp.rst
+++ b/llvm/docs/AMDGPU/gfx7_src_exp.rst
@@ -19,7 +19,7 @@
 
 An example:
 
-.. code-block:: nasm
+.. parsed-literal::
 
   exp mrtz v3, v3, off, off compr