[AMDGPU] Do not require opencl triple environment for OpenCL

A recent change requires opencl triple environment for compiling OpenCL
program, which causes regressions in libclc.

This patch fixes that. Instead of deducing language based on triple
environment, it checks LangOptions.

Differential Revision: https://reviews.llvm.org/D33445

llvm-svn: 303644
diff --git a/clang/test/CodeGenOpenCL/amdgpu-alignment.cl b/clang/test/CodeGenOpenCL/amdgpu-alignment.cl
index 714e724..70a22c9 100644
--- a/clang/test/CodeGenOpenCL/amdgpu-alignment.cl
+++ b/clang/test/CodeGenOpenCL/amdgpu-alignment.cl
@@ -1,4 +1,5 @@
 // REQUIRES: amdgpu-registered-target
+// RUN: %clang_cc1 -triple amdgcn-unknown-unknown -S -disable-llvm-passes -emit-llvm -o - %s | FileCheck %s
 // RUN: %clang_cc1 -triple amdgcn-unknown-unknown-opencl -S -disable-llvm-passes -emit-llvm -o - %s | FileCheck %s
 
 #pragma OPENCL EXTENSION cl_khr_fp64 : enable