Fix docs/Coroutines.rst syntax highlighting on Linux
Fix docs/Coroutines.rst syntax highlighting on Linux

Summary:
s/code-block:: C++/code-block:: c++ in docs/Coroutines.rst .

Patch by Gor Nishanov!  Edited by Sanjoy to fix a missing s/C/c/.

Reviewers: sanjoy, rengolin

Differential Revision: https://reviews.llvm.org/D22832

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@276806 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,apple/swift-llvm,llvm-mirror/llvm,apple/swift-llvm,llvm-mirror/llvm,llvm-mirror/llvm,apple/swift-llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,apple/swift-llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,GPUOpen-Drivers/llvm,apple/swift-llvm