[OpenCL] Fixes failures in test/Driver/opencl.cl.

Also fixes strict-aliasing option to only be allowed when OpenCL Version 1.0. Added testcase in test/Frontend/opencl-blocks.cl.

Patch by Aaron En Ye Shi.

Differential Revision: http://reviews.llvm.org/D22170

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@275318 91177308-0d34-0410-b5e6-96231b3b80d8